Bertrand Charrier

Eric Tardin

Charline Lanvin

Nabila Boutahar

Daniel Guibal

Keywords: II Energetic valorization of sugarcane bagasse via slow pyrolysis, means clustering, test, 108

other compounds ..... 2.3 Conclusion ...

CONTENTS

 [START_REF] Mohan | Pyrolysis of wood/biomass for bio-oil: a critical review[END_REF].... 1.4 Basic units of lignin ........................ 1.5 Proximate analysis results from typical biomass and coal samples [START_REF] Cai | Review of physicochemical properties and analytical characterization of lignocellulosic biomass[END_REF] ....................... 1.6 Variation ranges of oxygen and carbon in the volatile matter of biomass and the more common fossil fuels with their Lower Heating Value (LHV) [START_REF] Fantini | Biomass availability, potential and characteristics[END_REF] .............. 1.7 Bagasse storage facility to generate heat and electricity [START_REF] Tomak | The wood preservative potentials of valonia, chestnut, tara and sulphited oak tannins[END_REF] ............................ 1.8 Biomass conversion using biochemical and thermochemical routes with some examples of the main products [START_REF] Ferreira | Biorefinery concept[END_REF] .. 1.9 Composition of lignocellulosic materials and their potential hydrolysis products with further degradation compounds (HMF = Hydroxymethylfurfural) [START_REF] Taherzadeh | Acid-based hydrolysis processes for ethanol from lignocellulosic materials: a review[END_REF] .. 1.10 Representation of the reaction pathway for biomass pyrolysis [START_REF] Venderbosch | Fast pyrolysis technology development[END_REF] .................. 1.11 TG (full lines) and DTG (dashed line) curves for cellulose, hemicellulose, and lignin at a heating rate of 10 • C/min [START_REF] Yang | Characteristics of hemicellulose, cellulose and lignin pyrolysis[END_REF][START_REF] Ronsse | Carbonization of biomass[END_REF] ................ 1.12 Pyrolysis products [START_REF] Guo | Bioenergy and biofuels: History, status, and perspective[END_REF] .............. 1.13 Soil amended by biochar called "terra preta" on the righti mproves the crop yield compare to unamended soil on the left [START_REF] Pecha | Pyrolysis of lignocellulosic biomass: oil, char, and gas[END_REF] ................. 1.14 Chemical compositions and product distribution of pyrolysis liquid [START_REF] Huber | Synthesis of transportation fuels from biomass: chemistry, catalysts, and engineering[END_REF] ....................

2.1

The three dimensional section of a tree trunk [START_REF] Li | Wood-polymer composites[END_REF] .... 2.2 Attack of fungi on wood: a) brown-rot [START_REF] Goodell | 15 fungi involved in the biodeterioration and bioconversion of lignocellulose substrates[END_REF]; b) white-rot (Auró 2016); c) soft-rot [START_REF] Mariano | Identification and control of wood-deteriorating fungi[END_REF]; d) blue stain [START_REF] Goodell | 15 fungi involved in the biodeterioration and bioconversion of lignocellulose substrates[END_REF]; and e) mold [START_REF] Imken | Resistance of different wood-based materials against mould fungi: a comparison of methods[END_REF]) . 2.3 The condesable vapors of slow pyrolysis process ........

General Introduction

Residual agricultural biomass possesses great potential in providing renewable sources for producing energy and materials. Sustainable utilization of this biomass can be implemented using the pyrolysis technology with the objective of energy densification (converting biomass into rich carbonaceous biochar) while also utilizing the by-product as protection agents for wood or biomaterials. The simple utilization of biomass may be through direct combustion to provide heat and power generation. However, such a technique results in low efficiency and produces a huge amount of CO 2 . In addition to that, biomass should be used immediately due to its susceptibility to biodegradation. The potential of lignocellulosic biomass for energy production can be advanced through biomass conversion by means of pyrolysis. This process transforms the organic materials by using heat in an oxygen-deficient environment, breaks down the biomass components, such as hemicellulose, cellulose, and lignin, into smaller compounds, producing solid (char), liquid, and gas fractions [START_REF] Mohan | Pyrolysis of wood/biomass for bio-oil: a critical review[END_REF]. By adjusting pyrolysis process parameters, such as temperature level, heating rate, and residence time, the quantity of the most desired products can be controlled [START_REF] Carrier | Comparison of slow and vacuum pyrolysis of sugar cane bagasse[END_REF].

From several types of pyrolysis, slow pyrolysis, or traditionally refers to as carbonization, have been widely implemented for a long time. In the slow pyrolysis scenario, biomass material is slowly heated to produce char, where the organic vapors would often just be passed as waste [START_REF] Bridgwater | A comparison of fast and slow pyrolysis liquids from mallee[END_REF]. However, past and recent studies have shown some interest in recovering this type of condensable organic vapors due to its large composition of bio-active chemicals such as acids, phenols, furans, and guaiacols compounds. This liquid fraction has various nomenclature in the literature, such as pyrolysis oil, pyrolysis liquid, bio-oil, liquid smoke, wood vinegar and wood distillates [START_REF] Bridgwater | Renewable fuels and chemicals by thermal processing of biomass[END_REF], and its properties could differ from one another depending on the pyrolysis parameters and feedstock used. As a matter of fact, in many Asian countries, slow pyrolysis has been long practiced producing both charcoal and liquid products [START_REF] Mathew | Pyroligneous acid-the smoky acidic liquid from plant biomass[END_REF]. Traditional farmers in such countries benefit from the liquid product by using it as a plant growth stimulant and bio-pesticides [START_REF] Tiilikkala | Future energy transitions for bagasse cogeneration: Lessons from multi-level and policy innovations in mauritius[END_REF].

On the other hand, wood has been massively utilized due to its excellent physical, mechanical, and chemical properties. Nevertheless, some timbers species have limited end-uses due to their susceptibility to threats from biological agents, i.e., fungi and insects. In this case, pyrolysis liquid could be an interesting option/way for wood protection. Several researchers reported that pyrolysis liquid has anti-fungal and anti-termite activity [START_REF] Oramahi | Antifungal and antitermitic activities of wood vinegar from oil palm trunk[END_REF][START_REF] Barbero-López | Pyrolysis distillates from tree bark and fibre hemp inhibit the growth of wooddecaying fungi[END_REF]. Moreover, it was reported that bio-oil could be considered an alternative to creosote, which is more advantageous since it does not contain polynuclear aromatic hydrocarbons (PAHs) (Temiz et al., 2013a), thus limiting the environmental impact. The use of the pyrolysis liquid products for wood protection in the literature is relatively scant and it has a high variability due to the different types of feedstock and method used. Therefore, in this study, we were focused on valorizing the pyrolysis liquid from slow pyrolysis, which generally served as a secondary product.

In this study, sugarcane bagasse, a fiber residue that remained after sugarcane processing, was used as the pyrolysis feedstock. The biomass is originated from Réunion Island and was chosen as the tropical biomass model. The choice of bagasse is determined by taking into account three points: its availability, its presence as a waste/by-product instead of primary materials, and the potential of its valorization. Moreover, to our knowledge there was no precedent research on pyrolysis liquid obtained from sugarcane bagasse for wood treatment application. Converting sugarcane bagasse into char for energy production could also tackle the seasonality and biodegradability of this biomass. Being a seasonal plant, bagasse needs to be stored if it is to be utilized outside of its peak harvesting time. Also, being ah y g r o s c o p i c material, bagasse is prone to moisture change during storage and subject to biodegradation [START_REF] Breccia | Degradation of sugar cane bagasse by several white-rot fungi[END_REF][START_REF] Dong | Sugarcane bagasse degradation and characterization of three white-rot fungi[END_REF]. To overcome these problems, the thermochemical conversion of bagasse can be applied by transforming it into carbon-rich char, which can subsequently be stored without any energy depletion. Additionally, up until now, few studies are focused on a biomass co-valorization processes coupling (i) the pyrolysis process to produce energy and gases, and (ii) the keeping and the valorization of condensable chemical compounds issued from this first thermochemical process into valuable chemical compounds, more particularly for their anti-fungal and anti-termite's activities. The main objectives of this work will be to:

1. Determine the optimum condition of the pyrolysis process parameter for co-producing char and pyrolysis liquid.

2. Evaluate the chemical composition and the anti-fungal and anti-termite activities of the selected pyrolysis liquid.

This thesis is divided into four parts. The first part is dedicated to the literature review on biomass valorization via pyrolysis and the potential of pyrolysis liquid for wood protection. The second and third parts cover the findings on the experimental works conducted in this study. The second part presents the work on the slow pyrolysis parameters (temperature, heating rate, and holding time) and their effect on the char properties and the yield of char and pyrolysis liquid, along with the chemical composition of pyrolysis liquid. Meanwhile, the third part provides the results on the anti-fungal and anti-termites of pyrolysis liquid in Petri-dishes bioassays, the development of paper area measurement using k-means clustering for the termites' test, and wood treatment using pyrolysis liquid. Finally, the last part presents the general conclusion on the work and findings, as well as the perspective for future work.

Part I Literature review

Chapter 1

Biomass Valorization via Pyrolysis

Overview of lignocellulosic biomass

Biomass includes all living organisms (plant or animal) as well as its organic products and waste. It is estimated that 100 billion tons of biomass were produced every year globally [START_REF] Sheldon | Green and sustainable manufacture of chemicals from biomass: state of the art[END_REF]. Example of biomass include:

• Agricultural products and residues: sugarcane bagasse, straw, and corn stalks.

• Forests: wood, bark, and sawdust.

• Municipal: Municipal Solid Waste (MSW), sewage sludge, and food waste.

• Energy crops: sorghum, poplar, switchgrass, and willow.

• Biological: animal waste and aquatic biomass (algae).

Plant biomass can be defined as any organic matter produced by a biological process that stems from plants. It contains energy that is firstly derived from the sun through photosynthesis. Plants use solar energy to convert carbon dioxide and water into carbohydrates that form the building block of biomass. The energy is stored in the chemical bonds of the structural component of biomass [START_REF] Mckendry | Energy production from biomass (part 1): overview of biomass[END_REF].

The term lignocellulosic biomass refers to plant dry matter, non-edible biomass, which are not used for food or feed, mainly composed of energy crops, forestry, and agricultural waste. Lignocellulosic biomass has great potential for energy and material application. It can be burned to produce heat, converted to generate electricity, or indirectly used to produce biofuels.

In this section, the chemical composition of lignocellulosic biomass, its properties regarding the utilization for energy, and an overview of sugarcane bagasse are presented.

Biomass Valorization via Pyrolysis 1.1. Overview of lignocellulosic biomass

Chemical composition of lignocellulosic biomass

Lignocellulosic biomass is composed of the three main building blocks, namely cellulose, hemicellulose, and lignin. As shown in Fig 1 .1, cellulose is packed together with hemicellulose and lignin, constituting the plant cell wall. Cellulose serves as the skeleton, providing mechanical strength for the plant structure. Hemicellulose contributes to strengthening the cell walls by surrounding the cellulose fibers and acts as the cell's cementing matter. Lignin works like an embedding material responsible for the structural rigidity and protects the cell wall from microbial degradation. Cellulose and hemicellulose are macromolecules made from different sugars, whereas lignin is an aromatic polymer synthesized from phenylpropanoid precursors [START_REF] Kataki | Feedstock suitability for thermochemical processes[END_REF]. Figure 1.1: Cellulose, hemicellulose, and lignin in plant cell wall [START_REF] Wang | Pyrolysis of biomass[END_REF] The contents of cellulose, hemicellulose, and lignin vary depending on the feedstock. Lignin content is typically higher in woody biomass, specifically for coniferous wood (softwood) than deciduous (hardwood) species. Table 1.1 presents the composition of cellulose, hemicellulose, and lignin from selected biomass.

Cellulose

Cellulose is the main constituent of plant cell walls, which can reach 40-60% depending on the type of biomass, and almost in the pure form in cotton. The general formula for cellulose is (C 6 H 10 O 5 ) n , where n is the degree of polymerization (DP). DP is the number of glucose units in a cellulose molecule, Biomass Valorization via Pyrolysis

Overview of lignocellulosic biomass

Lignin has an amorphous structure, leading to many possible linkages between individuals, including ether bonds, carbon-carbonb o n d s ,a n de ster bonds. Ether bonds predominate between lignin units, accounting for 60-70% of the total linkages, whereas carbon-carbon bonds account for 30-40%. The ester bond content in the lignin structure is low and is primarily found in herbaceous plants [START_REF] Mohan | Pyrolysis of wood/biomass for bio-oil: a critical review[END_REF][START_REF] Wang | Lignocellulosic biomass pyrolysis mechanism: a state-of-the-art review[END_REF].

Extractives and inorganic compounds

Apart from the three major cell wall constituents, biomass also contains low molecular weight substances composed of various organic matter (extractives) and inorganic matter (ash). These compounds are the non-structural components that do not constitute the cell walls.

Extractives are the chemical compounds that can be extracted by nonpolar solvents (such as toluene and hexane) or polar solvents(suc hasw ater, alcohol, and methylene chloride). These include waxes, fat, tannins, resins, starches, essential oils, simple sugars, gums, saponins, and phenolics. Extractives function as intermediates in metabolisms, as energy reserves, and as defenses against microbial and insect attack [START_REF] Mohan | Pyrolysis of wood/biomass for bio-oil: a critical review[END_REF].

A small amount of inorganic mineral content is also found in lignocellulosic biomass, such as calcium, potassium, magnesium, sodium, silicon, sulfur, and chlorine. Traces of aluminum, titanium, manganese, iron, cobalt, copper, zinc, and other heavy metals may also be present [START_REF] Wang | Lignocellulosic biomass pyrolysis mechanism: a state-of-the-art review[END_REF]. Agricultural residues generally contain more inorganics than woody biomass.

Biomass properties

Proximate and ultimate (or elemental) composition are the two common types of analysis used in the thermal conversion. Proximate analysis of biomass gives the amount of (a) moisture; (b) fixed carbon, the non-volatile biomass fraction; (c) volatile matter, the condensable vapor and permanent gas (except water vapor) released from biomass when it is heated; and (d) ash, the inorganic residue remains after combustion. Fig. 1.5 demonstrates the proximate analysis results from typical biomass and coals a m p l e s . I t indicates that woody biomass and sugarcane bagasse contain higher volatile matter, while rice husk and straw contain higher ash, in comparison with other biomass. Figure 1.5: Proximate analysis results from typical biomass and coal samples [START_REF] Cai | Review of physicochemical properties and analytical characterization of lignocellulosic biomass[END_REF] The ultimate analysis aims to determine the contents of carbon, hydrogen, nitrogen, sulfur, and oxygen. Biomass is mainly composed of carbon (C), hydrogen (H), and oxygen (O), with a total content of above 95%. It also contains a smaller amount of nitrogen (N) and sulfur (S). Compared to fossil fuels, biomass is characterized by lower carbon content (thus lower heating value), higher hydrogen and oxygen content, and a much lower nitrogen and sulfur content. Biomass contains more volatile components and is more reactive than coal, which is explained by the O/C and H/C ratios in the Van Krevelen diagram (Fig. 1.6).

Figure 1.6: Variation ranges of oxygen and carbon in the volatile matter of biomass and the more common fossil fuels with their Lower Heating Value (LHV) [START_REF] Fantini | Biomass availability, potential and characteristics[END_REF] Several important properties related to the energy conversion processes are discussed below:

a. Moisture content

The moisture content in biomass can be present in two forms: (a) inherent or equilibrium, the moisture that is absorbed with the cell walls (does not depend on the weather condition); and (b) free or external, the moisture which is influenced by the weather condition during harvesting. Moisture drains much of deliverable energy from the conversion process, as the energy used in evaporation can not be recovered [START_REF] Mckendry | Energy production from biomass (part 1): overview of biomass[END_REF][START_REF] Cai | Review of physicochemical properties and analytical characterization of lignocellulosic biomass[END_REF].

b. Calorific value

Calorific value or heating value is the total energy released as heat during combustion and is commonly measured in terms of energy content per unit mass (MJ/kg). Depending on the physical state of the water present in the combustion products, two heating value types can be distinguished: higher heating value (HHV) and lower heating value (LHV). HHV is defined as the total amount of heat, including the latent heat contained in the water vapor. The LHV does not include the latent heat of water vaporization [START_REF] Mckendry | Energy production from biomass (part 1): overview of biomass[END_REF][START_REF] Cai | Review of physicochemical properties and analytical characterization of lignocellulosic biomass[END_REF]. Compared to fossil fuel, the biomass heating value is lower due to the large presence of oxygenated bonds.

c. Proportion of fixed carbon and volatiles

Biomass with a high volatile matter has the highest conversion than biomass with high fixed carbon [START_REF] Dhyani | A comprehensive review on the pyrolysis of lignocellulosic biomass[END_REF]. The importance of fixed carbon and volatile matter is the measure for the ease of ignition and further gasification or oxidation, depending on how biomass will be used as an energy source [START_REF] Mckendry | Energy production from biomass (part 1): overview of biomass[END_REF].

d. Ash and alkali metal content

The biomass ash content can affect both handling and processing cost in the biomass energy conversion. As has been previously mentioned, the primary ingredients of biomass ash include the oxide form of silica aluminum, calcium, magnesium, iron, sodium, titanium, and sodium. The presence of alkali metal such as potassium or halides such as chlorine may play a significant role in serious agglomeration, fouling, and corrosion in boilers or gasifiers [START_REF] Fantini | Biomass availability, potential and characteristics[END_REF]. Also, alkali metals and silica's reaction may produce a sticky, mobile liquid phase, leading to blockage of airways in the furnace and boiler plant [START_REF] Mckendry | Energy production from biomass (part 1): overview of biomass[END_REF].

e. Cellulose/lignin ratio

The ratio between cellulose and lignin is important only in biochemical processes due to the higher biodegradability of cellulose than that of lignin. This is significantly related to the feedstock selection for such conversion (see further about the biochemical process in subsection 1.2.1).

Sugarcane bagasse

Sugarcane (Saccharum spp.) is a perennial monocotyledonous plant, belongs to the grass family, Poaceae and native to the warm temperate to tropical regions of India, Southeast Asia, and New Guinea. It is an important agricultural commodity cultivated in many countries. The extraction of juice to produce sugar in sugar mill resulted in the fiber residue called bagasse, which is considered its primary by-product. Generally, one ton of raw sugarcane can produce about 100 kg of sugar, approximately 270 kg of dry bagasse, and about 35 kg of molasses [START_REF] Garcia-Perez | Sugarcane bagasse vacuum pyrolysis[END_REF].

Bagasse is obtained after the extraction of sugar juice for the production of sugar and ethanol. Bagasse is a lignocellulosic residue, thus classifying it into the second generation biofuel, meaning that it does not compete with food crop production. Bagasse is a highly heterogeneous material consist of 50 wt% true fiber, 15 wt% fibrovascular bundles, 30 wt% pith, and 5 wt% Biomass Valorization via Pyrolysis 1.1. Overview of lignocellulosic biomass wax based on its dry weight. The chemical composition of bagasse varies between 27 and 50% cellulose, 20 and 35% hemicellulose, 10 and 25% lignin, and 1 to 6% ash on a dry weight basis [START_REF] White | Biomass pyrolysis kinetics: a comparative critical review with relevant agricultural residue case studies[END_REF]. At present, in most of the sugar industry, bagasse is mostly used for generating heat and electricity [START_REF] José | Differences in the chemical structure of the lignins from sugarcane bagasse and straw[END_REF]. By combusting the biomass directly, large quantity of bagasse will not be practical to store because it is susceptible to degradation if stored too long in warm humid conditions. Through thermochemical process, bagasse will extend its uses to high energy density products. Storage, transport volume, and the degradation of energy resource will be greatly reduced by the implementation of pyrolysis as energy densification method [START_REF] Hugo | Pyrolysis of sugarcane bagasse[END_REF].

Biomass Utilization and Valorization

Biomass is a versatile material that has been used by humankind since dawn time. Even now, biomass is still used as the primary energy sources in many developing countries and contributed 10 % of the world's energy supply [START_REF] Popp | Bioeconomy: Biomass and biomass-based energy supply and demand[END_REF].

Principally, to produce energy, biomass can be exploited in two forms, namely traditional biomass, and modern biomass. The so-called modern biomass is often characterized as the more sustainable biomass utilization method, including electricity generation, heat production, and transportation fuels. On the contrary, traditional biomass is produced in an unsustainable manner and is still the primary use form in most islands and many developing countries [START_REF] Goldemberg | Renewable energy-traditional biomass vs. modern biomass[END_REF]. Biomass for energy can be directly used or converted in different forms such as solid, liquid, or gaseous products. Primary solid biofuels include wood chips, pellets, charcoal, and fuelwood for cooking and heating in many developing regions. Liquid biofuels include bioethanol and biodiesel, usually used for transportation purposes. Meanwhile, gaseous biofuels cover biogas generated by anaerobic digestion of organic wastes and syngas from gasification [START_REF] Guo | Bioenergy and biofuels: History, status, and perspective[END_REF].

In this section, the general overview of biomass conversion technology is reviewed. State of the art on the pyrolysis process and its products is also presented.

Conversion of biomass

Biomass valorization can be defined as transforming the biomass and various residues into energy, fuels, and other useful materials, focusing on environmental indicators and sustainability goals [START_REF] Nzihou | Toward the valorization of waste and biomass[END_REF]. Lignocellulosic biomass can be converted in the following ways: (a) direct combustion to produce heat or (b) converted into biofuels and valuable hydrocarbons.

Direct combustion

Direct combustion is the simplest and most common method of utilizing biomass to generate heat but results in low energy efficiency (15-30 %). This approach also leads to undesirable ash buildup and produces a considerable amount of CO 2 as its by-product. The heat produced must be exploited immediately because storage is not a viable option [START_REF] Bridgwater | Renewable fuels and chemicals by thermal processing of biomass[END_REF].

Another option to utilize biomass is through conversion using biochemical or thermochemical pathways (Fig 1.8). The comparison between the two conversion methods is provided in Tab. 1.2. Figure 1.8: Biomass conversion using biochemical and thermochemical routes with some examples of the main products [START_REF] Ferreira | Biorefinery concept[END_REF]

Biochemical conversion

Biochemical conversion converts the holocellulose (hemicellulose and cellulose) into simple sugars through a process called hydrolysis (Fig. 1.9). These sugars are intermediate products that can be fermented into various valueadded chemicals. The most common biochemical conversions are fermentation and anaerobic digestion.

Thermochemical conversion

Thermochemical conversion is the controlled heating or oxidation of biomass as part of several pathways to produce intermediate energy products, which can also be upgraded to valuable products [START_REF] Tanger | Biomass for thermochemical conversion: targets andc h a l l e n g e s[END_REF]. Combustion (complete oxidation), gasification (partial oxidation), and pyrolysis (thermal degradation without oxygen) are examples of thermochemical conversion. Tab. 1.3 presents the types of the thermochemical conversion process.

It is important to differentiate pyrolysis from gasification as the latter decomposes biomass to syngas by carefully controlling the amount of oxygen present [START_REF] Mohan | Pyrolysis of wood/biomass for bio-oil: a critical review[END_REF]. Pyrolysis is also the first step in combustion Table 1.2: Comparison between biochemical and thermochemical conversion of biomass

Biochemical conversion

Thermochemical conversion

• Using enzymes and microorganisms.

• Process takes time (in the range of days) to complete.

• Convert carbohydrates (hemicellulose and cellulose) into sugar.

Produce lignin as a by-product.

• Using heat and catalyst.

• Process occur faster (in a few seconds to hours).

• Utilize the whole feedstock to produce value-added hydrocarbons (not feedstock specific). and gasification processes, followed by total or partial oxidation of the primary products. Further, pyrolysis can be categorized into different types depending on the operating parameters and desired products.P y r o l y s i si s usually classified based on the heating rate (slow or fast). Slow pyrolysis, which may also be similar to conventional pyrolysis (carbonization), occurs at a low heating rate and long vapor residence time, and is intended to produce charcoal or solid product primarily. It also covers torrefaction, a low-temperature pyrolysis process that usually serves as a pretreatment process. Torrefied biomass has a typical higher energy content than the original feedstock and requires less energy to grind. On the other hand, fast pyrolysis occurs at a high heating rate and short vapor residence time (less than 2 seconds). It targeted the liquid, named bio-oil, as the main product, where its yield can reach up to 70 wt% [START_REF] Bridgwater | A comparison of fast and slow pyrolysis liquids from mallee[END_REF]. Another conversion technique, such as a thermo-catalytic conversion, can also be considered. The examples include the Fischer-Tropsch synthesis (convert syngas obtained by gasification into liquid transport fuels) and liquefaction [START_REF] Ferreira | Biorefinery concept[END_REF].

Biomass pyrolysis and its mechanisms

Among several types of thermochemical pathways mentioned earlier, pyrolysis has been extensively studied as a promising route to produce fuels and chemicals from biomass. Pyrolysis is a term used to describe a thermal decomposition of organic materials in the absence or a poor oxygen condition so that it is highly unlikely for the complete combustion to occur [START_REF] Mohan | Pyrolysis of wood/biomass for bio-oil: a critical review[END_REF]. The word pyrolysis originated from the two Greek words: pyro, meaning "fire," and lysis, meaning "separating." Biomass pyrolysis is a very complex mechanism. The complexity stems from variations in the decomposition of biomass components with varying reaction mechanisms and reaction rates. Fig. 1.10 shows the reaction pathway for biomass pyrolysis. It is commonly accepted that biomass pyrolysis follows three steps mechanisms: (i) dehydration, the initial evaporation of free moisture; (ii) primary reaction, which is responsible for the largest biomass degradation, forming the solid char at 200-400 • C; and (iii) secondary reaction (e.g., cracking and repolymerisation of primary volatile compounds), which continues in a solid matrix with a further increase in temperature (>400 • C) [START_REF] Fisher | Pyrolysis behavior and kinetics of biomass derived materials[END_REF][START_REF] Kan | Lignocellulosic biomass pyrolysis: A review of product properties and effects of pyrolysis parameters[END_REF]. The secondary reactions are only predominant if sufficient vapor residence times are allowed (>1s), such as in the slow pyrolysis case [START_REF] Ronsse | Carbonization of biomass[END_REF]. Moreover, it is likely that primary char (the solid product from the primary reaction) acts as catalyst for the cracking organic vapors, forming additional char (secondary char), non-condensable gases, and water, thus lowering the bio-oil yield [START_REF] Bridgwater | Principles and practice of biomass fast pyrolysis processes for liquids[END_REF]. In case of fast pyrolysis, the secondary reaction is prevented to maximize the bio-oil yield by rapid heating of biomass as well as rapid removal and rapid quenching of the condensable vapors [START_REF] Venderbosch | Fast pyrolysis technology development[END_REF].

Figure 1.10: Representation of the reaction pathway for biomass pyrolysis [START_REF] Venderbosch | Fast pyrolysis technology development[END_REF] During pyrolysis, cellulose, hemicellulose, and lignin undergo their own reaction pathways, such as cross-linking, depolymerization, and fragmentation at their temperature, producing solid, liquid, and gaseous products. The decomposition behavior of biomass during pyrolysis is commonly observed using thermal analysis, including thermogravimetric analysis (TGA) and differential scanning calorimetry. In general, the process begins with moisture evolution followed by the hemicellulose, cellulose, and lignin decomposition. [START_REF] Venderbosch | Fast pyrolysis technology development[END_REF]. Hemicellulose has low thermal stability due to its amorphous properties and low degree of polymerization. It gives rise to more volatiles, less char, and less tar in contrast to cellulose. Decomposition of hemicellulose primarily results in the release of methanol, acetic acid, and acetone. At around 320 • C, the more stable cellulose starts to decompose [START_REF] Ronsse | Carbonization of biomass[END_REF]. At temperature higher than 400 • C, almost all cellulose was pyrolyzed [START_REF] Yang | Characteristics of hemicellulose, cellulose and lignin pyrolysis[END_REF] and converted to non-condensable gas and condensable organic vapor, with levoglucosan as the main pyrolysis product. Lignin decompose slowly under a wide temperature range between 160 • C and 900 • C, producing the highest residual char. It also yields phenols and heavy tars (larger molecular fragments) via the cleavage of ether and carbon-carbon linkages [START_REF] Mohan | Pyrolysis of wood/biomass for bio-oil: a critical review[END_REF][START_REF] Ronsse | Carbonization of biomass[END_REF].

Several parameters such as biomass type, biomass particle size, temperature, heating rate, vapor residence time, and reaction atmosphere influence the biomass pyrolysis process, yields, and products' properties. As previously stated, the pyrolysis of each biomass constituent has a unique reaction pathway and thermochemical characteristics. Cellulose and hemicellulose contribute mostly to bio-oil yield, while lignin yields a large proportion of char. Smaller biomass size particles promote the intraparticle heat and mass transfer to form uniform temperature during pyrolysis, thus augment the bio-oil yield. The temperature at the range from 400-550 • C maximized the solid and liquid products, then decreased with the increased heating. Higher heating rates promote higher liquid yield, while lower heating rates favor the production of char. The slightly oxidized atmosphere and increased residence time promote gasification and reduce the liquid yield [START_REF] Kan | Lignocellulosic biomass pyrolysis: A review of product properties and effects of pyrolysis parameters[END_REF].

Pyrolysis products: properties and applications

During pyrolysis, exposure to the high-temperature resultsi nt h eb r e a kdown of biomass chemical constituents (cellulose, hemicellulose, and lignin), producing solid char (biochar), vapor condensate (liquid bio-oil), and noncondensable vapor (syngas) (Fig. 1.12). Below the characteristics and the potential uses of the three pyrolysis products are discussed.

Figure 1.12: Pyrolysis products [START_REF] Guo | Bioenergy and biofuels: History, status, and perspective[END_REF] 1.

Solid product

A solid product from pyrolysis (char) is a carbonaceous material that is commonly combusted to produce heat, steam, or electricity. The term "charcoal" is typically used when the intended purpose is to use it as a fuel or as a reducing agent in a metallurgical smelting point. The heating value of char ranges from 15 to 30 MJ/kg. The high heating value makes char attractive to be used for the fuel application. When combusted, ash would remain. The remaining ash found its application in cement production [START_REF] Pecha | Pyrolysis of lignocellulosic biomass: oil, char, and gas[END_REF].

Another interest is to use char as a low-cost adsorbent, carbon sequestration, and soil amendment. "Biochar" is a common term used in the literature for the soil application interest. Char has unique surface properties and has an extensive porous structure with comparatively high surface area-to-weight ratios to be used as a potential low-cost adsorbent for CO 2 capture [START_REF] Creamer | Carbon dioxide capture using biochar produced from sugarcane bagasse and hickory wood[END_REF]. Char has recalcitrant nature, very stable when stored in the soil, and resistant to biological decay; thus, it can store carbon and prevents the rapid release of CO 2 if the biomass would be kept untreated [START_REF] Woolf | Sustainable biochar to mitigate global climate change[END_REF]. Char is also believed to increase soil productivity through its unique physicochemical properties. The highly porous char lead to the increase of water holding capacity and soil's aeration. Moreover, it provides a favorable habitat for beneficial soil microorganisms, increasing soil microbial activity [START_REF] Laird | Review of the pyrolysis platform for coproducing bio-oil and biochar[END_REF][START_REF] Vanholme | Towards a carbonnegative sustainable bio-based economy[END_REF]. Fig. 1.13 shows how biochar application can enhance soil quality for agricultural purposes.

Liquid product

Liquid fractions from pyrolysis consist of a complex mixture of water and an organic phase containing many chemical compounds, such as acids, alcohols, aldehydes, ketones, ethers, esters, phenols, sugars, alkenes, furans, nitrogen compounds, and miscellaneous oxygenate [START_REF] Kan | Lignocellulosic biomass pyrolysis: A review of product properties and effects of pyrolysis parameters[END_REF]. The chemical composition of the pyrolysis product is highly dependent on the variation in the composition of the biomass feedstock. Fig. 1.14 illustrates the chemical compositions and product distribution of pyrolysis liquid. The final water content depends on the initial moisture content of biomass and water formation during pyrolysis, ranging from ∼15 wt% to an upper limit ∼30-50 % [START_REF] Mohan | Pyrolysis of wood/biomass for bio-oil: a critical review[END_REF]. This product can be considered a micro-emulsion, forming a stable monophasic mixture. The aqueous solution (notably originated from the holocellulose decomposition) acts as a continuous phase that stabilizes the discontinuous phase of pyrolytic lignin macro-molecules through mechanisms such as hydrogen bonding [START_REF] Mohan | Pyrolysis of wood/biomass for bio-oil: a critical review[END_REF][START_REF] Bridgwater | Review of fast pyrolysis of biomassa n dp r o d u c t upgrading[END_REF]. This liquid fraction has various nomenclature in literature, such as pyrolysis oil, bio-oil, liquid smoke, wood distillates, pyroligneous tar, and pyroligneous acid [START_REF] Bridgwater | Renewable fuels and chemicals by thermal processing of biomass[END_REF].

Figure 1.14: Chemical compositions and product distribution of pyrolysis liquid [START_REF] Huber | Synthesis of transportation fuels from biomass: chemistry, catalysts, and engineering[END_REF] Tab. 1.4 shows typical physical properties of wood pyrolysis bio-oil. The Table 1.4: Typical properties of wood pyrolysis bio-oil [START_REF] Bridgwater | Renewable fuels and chemicals by thermal processing of biomass[END_REF] elemental composition of pyrolysis liquid resembles the biomass, which contains a large oxygen content (45-50%). The higher heating value (HHV) of pyrolysis liquid thus considerably low, ranges between 15-20 MJ/kg, compared to the petroleum oils (42-45 MJ/kg) [START_REF] Kan | Lignocellulosic biomass pyrolysis: A review of product properties and effects of pyrolysis parameters[END_REF]. Although the pyrolysis liquid is often called bio-oil or pyrolytic oil, inf a c t ,i th a sah i g h polarity and has a hydrophilic nature; thus, it is not miscible with liquid hydrocarbons. Pyrolysis liquid is miscible with polar solvents such as acetone, ethanol, and methanol but cannot be dissolved in water [START_REF] Mohan | Pyrolysis of wood/biomass for bio-oil: a critical review[END_REF]. It can tolerate the addition of some water until the phase separation occurs.

Other undesirable properties of pyrolysis liquid are low pH (2)(3), which can be corrosive to common structures. Pyrolysis liquid contains a substantial amount of carboxylic acids such as acetic acid and formic acid that contribute to the acidic properties. It is also chemically unstable during storage due to the ongoing chemical reactions to form large molecules such as polymerization, etherification, and esterification, where the instability increases with heating [START_REF] Mohan | Pyrolysis of wood/biomass for bio-oil: a critical review[END_REF][START_REF] Kan | Lignocellulosic biomass pyrolysis: A review of product properties and effects of pyrolysis parameters[END_REF].

Pyrolysis liquid can be used in energy applications such as being combusted in residential or industrial boilers, co-fired with natural gas or coal for power generation, blended with either ethanol or gasoline, or converted into fuels and chemicals through hydrocracking/hydroprocessing [START_REF] Roy | Prospects for pyrolysis technologies in the bioenergy sector: A review[END_REF]. Bio-oil upgrading by steam reforming and gasification can produce combustible syngas and hydrogen. Bio-oil can also be used as feedstock to produce chemicals, such as phenols for resin production, flavoring agents (i.e., glycolaldehyde) in food industries, and additives in fertilizing and phar-maceutical industries [START_REF] Kan | Lignocellulosic biomass pyrolysis: A review of product properties and effects of pyrolysis parameters[END_REF]. Another utilization of pyrolysis liquid related to pesticide and wood preservation is discussed particularly in Chapter 2.

Gaseous product

Pyrolysis gas mainly contains several combustible gases, including H 2 , CO, CH 4 , and C 2 -hydrocarbons, with a high concentration of incombustible CO 2 [START_REF] Crombie | Investigating the potential for a selfsustaining slow pyrolysis system under varying operating conditions[END_REF]. CO and CO 2 are the main products of pyrolysis that originated from the decomposition and reforming of carbonyl (C=O) and carboxyl (COO) groups and are preferably produced at low temperatures. H 2 is generated from the secondary decomposition and reformingo f the aromatic C=C and C-H groups at high temperatures. Meanwhile, the light hydrocarbons (CH 4 ) are mainly due to the decomposition of weakly bonded methoxyl and methylene, and the secondary decomposition of the oxygenated compounds [START_REF] Qu | Experimental study of biomass pyrolysis based on three major components: hemicellulose, cellulose, and lignin[END_REF][START_REF] Kan | Lignocellulosic biomass pyrolysis: A review of product properties and effects of pyrolysis parameters[END_REF].

The heating value of pyrolysis gas is relatively low (6.4-9.8MJ/kg) [START_REF] Varma | Pyrolysis of sugarcane bagasse in semi batch reactor: Effects of process parameters on product yields and characterization of products[END_REF]. It can be regarded as a low-energy-density product (6 MJ/kg), compared to liquid and solid products [START_REF] Crombie | Investigating the potential for a selfsustaining slow pyrolysis system under varying operating conditions[END_REF]. Instead of using it for heat production and power generation,p yrolysisgasis potentially used to sustain the pyrolysis system, such as forh e a t i n gt h eu n i t or to dry the feedstock [START_REF] Becidan | Products distribution and gas release in pyrolysis of thermally thick biomass residues samples[END_REF].

Conclusion

In this chapter, the importance and potential of biomass valorization through pyrolysis have been presented. The biomass conversion, especially from agricultural waste, offers benefits in producing value-added products. As mentioned, pyrolysis liquid serves a wide variety of applications, including its potential for wood protection. In the next chapter, the literature review will focus on the pyrolysis liquid potential for wood protection. An introduction to wood as a material and its relationship to natural durability, biological degradation, and various protection methods are discussed. Several past studies dealing with pyrolysis liquid for wood protection are also reviewed.

Chapter 2

Pyrolysis Liquid for Wood Protection

Wood Protection

For millennia, wood has been used by humankind, which played a vital role in civilization's history and the world's economy. It is becoming the primary source of numerous applications, from its utilization as fuel for cooking and heating to raw material for constructions, engineered products, furniture, paper, and chemical sources. Moreover, wood is the only building material that can be regrown. Sustainably, by converting wood into products, wood continues to store carbon, and by replanting the trees, carbon dioxide was removed from the atmosphere by the natural process of the carbon cycle during photosynthesis. Nonetheless, wood can be degraded by weathering (abiotic factor) and biological degradation (biotic factor). Wood is also hygroscopic due to the hydroxyl group's presence, which means that it attracts or releases water from the surrounding environment until it reaches equilibrium. This hygroscopic character can render wood with poor dimensional stability. Also, in a condition where the moisture content is suitable, fungi can grow and decay the wood. All of these undesirable properties limit the utilization of wood in terms of its durability or quality. Thus, various wood preservation or wood protection methods have been developed to extend the wood's service life.

This section discusses the importance of wood protection related to its biological degradation and protection methods.

Wood as a material and its natural durability

Wood is a type of lignocellulosic biomass composed of cellulose, hemicellulose, and lignin as its major structural component. It also contains mineral matters (ash) and extractive. Based on its dry weight, wood consists mainly of sugarbased polymers (carbohydrates, 65-75%) combined with lignin (18-35%). In total, dry wood has an elemental composition of about 50% carbon, 6% hydrogen, 44% oxygen, and trace amounts of inorganics. Generally, the conif-Pyrolysis Liquid for Wood Protection 2.1. Wood Protection biological attack, mainly due to the extractives [START_REF] Taylor | Heartwood formation and natural durability-a review[END_REF]. Biological resistance can be given to a certain extend by lignin content [START_REF] Miedes | The role of the secondary cell wall in plant resistance to pathogens[END_REF]. Wood containing a high amount of silica (Si) can also be more resistant, especially to insect [START_REF] Ghosh | Resistance of scots pine (pinus sylvestris l.) wood modified with functionalized commercial silicone emulsions against subterraneant e r m i t e s[END_REF]. European standard EN 350 (2016) provides the durability class corresponding to the natural resistance of wood species. Today, the reduced availability of naturally durable wood species increases reliance on the use of fast-grown non-durable wood, thus requiring protection treatment to lengthen their service life.

Biological degradation of wood

As biological material, wood is susceptible to various deteriorating organisms when exposed to various environments. At the same time, however, wood decomposition by biological organisms is essential for the ecosystem as it is part of nature's carbon cycle. Fungi (particularly basidiomycetes and soft rots), insects, and marine borers are the type of organisms that can cause severe damage to wood.

Fungi

Tab. 2.1 provides the summary of the main types of fungi that can colonize and degrade wood, with some images of attacked wood illustrated in Fig.

2.2.

The fungi that degrade wood and causing decay can be classified into brown-rot, white-rot, and soft-rot. Decay fungi need food (hemicellulose, cellulose, and lignin), oxygen, moisture (above the fiber saturation point; about 30 % moisture content), and suitable temperature (10 [START_REF] Ibach | Biological properties[END_REF]. These fungi degrade the wood cell wall's structural polymer by secreting enzymes that can break down the wood lignocellulosic constituents into simple molecules that can be metabolized and absorbed by their hyphae's membrane. In principle, carbohydrates of cellulose and hemicellulose are more easily degraded, while lignin is more resistant to most microorganisms because of the structure of the phenylpropane units and the strong bonds between the units. The hydrophobic nature of lignin prevents the diffusion of enzyme degradation inside the large three-dimensional molecules. Lignin is effectively degraded by the type of white-rot fungus, while it serves as a barrier against wood decay for other microorganisms [START_REF] Schmidt | Wood and tree fungi[END_REF]. Table 2.1: Main types of fungi that can colonize and degrade wood [START_REF] Blanchette | A review of microbial deterioration found in archaeological wood from different environments[END_REF][START_REF] Ibach | Biological properties[END_REF][START_REF] Broda | Natural compounds for wood protection against fungi-a review[END_REF][START_REF] Goodell | Fungal degradation of wood: Emerging data, new insights and changing perceptions[END_REF] Brown-rots depolymerize cellulose rapidly during the initial stages of wood colonization. They cause dramatic strength loss in early decay stages, often before decay characteristics are visually evident. White-rots can degrade all cell wood constituents. Compared to brown-rot, the strength losses occur more slowly and not significant until the late decay stages. They typically erode the cell from the cell lumen outward by breaking down successive layers of cell walls. Hence, the wood becomes progressively thinner with greater weight loss at the later decay stage, which can up to 97%. Softrots cause progressive degradation from the wood surface inward. As decay progresses, extensive carbohydrate loss occurs with increasing lignin concen- [START_REF] Goodell | 15 fungi involved in the biodeterioration and bioconversion of lignocellulose substrates[END_REF]; and e) mold [START_REF] Imken | Resistance of different wood-based materials against mould fungi: a comparison of methods[END_REF] trations in the residual wood. Extremely poor strength characteristics are observed when soft-rotted wood is visually apparent due to the significant cellulose degradation and cavity formation in the wood [START_REF] Blanchette | A review of microbial deterioration found in archaeological wood from different environments[END_REF][START_REF] Shmulsky | Forest products and wood science: an introduction[END_REF][START_REF] Goodell | Fungal degradation of wood: Emerging data, new insights and changing perceptions[END_REF].

• C to 35 • C; op- timum 24 • C to 32 • C) to grow
Other types of fungi such as mold and blue stain can also attackw o o d , causing only damage to the wood surface and affecting wood's aesthetic value due to wood discoloration. However, they do not significantly cause structural damage to wood. Simple drying to less than 20 % moisture content is often sufficient to protect the wood from these types of fungi.

Insects

The most important wood-destroying insects are beetles (order Coleoptera) and termites (order Isoptera). Beetles only degrade wood during their larval stage and mainly degrade sapwood or all wood when there is no difference between sapwood and heartwood, such as beech (Fagus sylvatica). They mainly degrade the starch, even if some beetles can degrade cellulose to a small extent [START_REF] Martin | Cellulose digestion in insects[END_REF].

Pyrolysis Liquid for Wood Protection

Wood Protection

Termites are probably the type of insects that cause the most damage to wooden structures. It is estimated that the global economic impact of this pest is counted for more than 40 billion annually, in which the subterranean termites contribute 80 % of the damage [START_REF] Rust | Managing social insects of urban importance[END_REF]. Based on their living environment, three main categories of termites can be distinguished: (i) subterranean termites, which live undergrounds; (ii) dry termites, which can live in the dry wood and do not need to be near the soil; and (iii) damp wood termites, which live in very moist wood and do not need soil to survive [START_REF] Govorushko | Economic and ecological importance of termites: A global review[END_REF]. All termites are eusocial insects, and they have three stages of metamorphosis (egg, nymph, and adult). Termites live in a colony made up of reproductives (kings, queens, and alates), soldiers, and workers. Each termite in the colony does a specific job that benefits the colony as a whole. The primary reproductives, a king and queen, were initially developed from winged forms (alates) that have left their parent colony and shed their wings to mate and build new colonies of their own. Nymphs can become alates, young winged reproductives with a black pigmentation. Depending on the climatic conditions, these alates will leave the nest in swarmers. Once they have fallen back to the ground and pair, they will establish a new colony by becoming king and queen [START_REF] Vargo | Diversity of termite breeding systems[END_REF]. The soldiers (adults) are responsible for defending the colony, and particularly the queen and the king. They represent about 10% of the colony. The workers (adults) are responsible for the formation of galleries in the wood, and therefore for its degradation. They make up about 90% of the colony, which their tasks are to care for the young, repair the nest, build foraging tunnels, locate food, and digest cellulose to feed the whole termites [START_REF] Bignell | Biology of termites: a modern synthesis[END_REF][START_REF] Miller | Subterranean termite biology and behavior[END_REF].

Marine borers

Marine borers can cause extensive damage to wood submerged in salt or brackish water. Crustaceans (gribbles) and mollusks (shipworms) are the most important. Gribbles or Limnoria spp are 3-5 mm long, and they settle on wood, forming superficial burrows less than 12 mm, but the borers continually bore in deeper with water erosion. The molluscan borers belong in the family Teredinidae and the genera Teredo or Bankia. The best-known genus is Teredo (shipworms). The young larvae can swim and eventually settle on wood where they boreholes about 0.5 mm in diameter [START_REF] Richardson | Wood preservation[END_REF][START_REF] Ibach | Biological properties[END_REF].

Pyrolysis Liquid for Wood Protection 2.1. Wood Protection

Principle of wood protection

The service life of wood products can be considerably extended by proper treatment or species selection. Wood products users must understand the conditions under which deterioration occurs and the appropriate preventive measures to be taken [START_REF] Shmulsky | Forest products and wood science: an introduction[END_REF]. European standard EN 335 (2013) defines the five use classes for different service situations on the solid wood and wood-based products, which correspond to more or less significant exposure to biological degradation agents (Tab. 2.2).

One of the important aspects of using wood while limiting its degradation is based on the idea of disrupting the principal physiological needs for microorganisms' growth and development. For instance, to avoid fungal decay, the wood must be kept dry, and this is most easily achieved by protecting it from rain (using rain barrier) and excess humidity (using vapor barrier) [START_REF] Richardson | Wood preservation[END_REF]. Serious decay can also come from the wrong choice of wood: natural durability is not adequate to resist the biological risk. Avoidance of moisture is thus a key principle for wood protection by design [START_REF] Mahnert | A review on the protection of timber bridges[END_REF]. In case of avoiding termites attack, for example, the best way to protect the wood can be achieved by preventing the termites from gaining hidden access to a building, such as making the foundation made from concrete with cement mortar [START_REF] Clausen | Biodeterioration of wood. Wood handbook: wood as an engineering material: chapter 14[END_REF].

However, in some conditions where the deterioration is inevitable and in order to comply with the desire service life of wooden commodities, protection treatments should always be used [START_REF] Ibach | Biological properties[END_REF]. The classical concept of wood preservation is to eliminate suitable nutrition by treating wood with biocide (active ingredients) that are toxic to wood-degrading organisms, thus preventing biological attacks. There are four basic requirements to ensure the level of protection from particular preservatives in the treatment process, including the toxicity (the effectiveness of chemical against biological organisms), permanence (the resistance of the preservative to leaching, volatilization, and breakdown), retention, and depth of penetration into the wood [START_REF] Ibach | Biological properties[END_REF].

It is also possible to use methods other than the application of toxic chemicals (for example, aiming not only to increase its durability but also to improve wood properties). Protecting wood from moisture variations (reducing the tendency of wood to take on moisture) and keeping the wood dimensionally stable can be achieved by applying water repellents and dimensional stabilizers. Such treatment can be categorized under two principles: whether it causes changes in the cell wall (refers to wood modification) or not [START_REF] Rowell | Water repellency and dimensional stability of wood[END_REF][START_REF] Sailer | Potential wood protection strategies using physiological requirements of wood degrading fungi[END_REF]). In the end, all of these treatments will ultimately depend on the final usage of wood products. a Border line and extreme cases of use of wood and wood-based products exist. This can cause the assignment of a use class that differs from that defined in this standard. b It may not be necessary to protect against all biological agents listed as they may not be present or economically significant in all service conditions in all geographic regions, or may not be able to attack some wood-based products due to the specific constitution of the product. c The above water portion of certain components can be exposed to all of the above biological agents.

History and development of wood preservation

The history of preserving wood can be traced to ancient Egypt and Roman times, where they use natural products from the extracted durable timbers or plants such as oil, resin, and tars. The Chinese used metallic salts as preservatives for the wood building materials by immersing them in seawater or salt lakes' water [START_REF] Thompson | The chemistry of wood preservation[END_REF][START_REF] Richardson | Wood preservation[END_REF]. In the 1700s to 1800s, various chemical formulations have been tested, including mercuric chloride, copper sulfate, and zinc chloride; however, they remain leached out in the water, limiting the use for the exterior applications [START_REF] Thompson | The chemistry of wood preservation[END_REF][START_REF] Freeman | Past, present, and future of the wood preservation industry[END_REF]. Major significant advances in industrial timber preservation were developed during the 19th century by using coal-tar creosote. The firstgeneration oil-borne preservatives, creosote, patented in 1836 by Franz Moll, is a by-product of coke production. During the industrial revolution, notably in the European countries, large volumes of sleepers and poles were treated by creosote through a pressure impregnation known as Bethell process (fullcell process), patented by John Bethell in 1838. In the early 19th century, creosote was made from beech wood tar, and distillation of coal tar began later [START_REF] Freeman | Past, present, and future of the wood preservation industry[END_REF].

Other major first-generation preservatives systems also include oil-borne pentachlorophenol and the water-borne arsenicals, predominantly chromated copper arsenate (CCA). Pentachlorophenol, formed by chlorine's reaction on phenol, was developed in the 1930s and widely used in industrial applications as an oil-borne preservative. On the other hand, the first-generation metallics CCA involved classical poison arsenic that kills wood-eating insects and copper, which are toxic to fungi. Chromium was added in the formulation as a chemical fixing agent, binding the two toxic metals through chemical complexes to the wood cell walls. CCA was broadly used for residential use from the 1970s to the early 2000s since it left timber with no surface residue or oily smell. However, in the 1990s, public perception of the toxicity risk for human health and its environmental impact on bioaccumulation and disposal concern led to the ban of toxic chemicals [START_REF] Schultz | A brief review of the past, present and future of wood preservation[END_REF].

The second-generation wood preservatives are water-borne copper-rich systems that contain amine-or ammonia-complexed alkaline copper(II) and an organic cobiocide. Various products based on organic or inorganic formulation such as alkaline copper quat (ACQ), copper azole (CA), and copper-HDO were the CCA substitutes for residential applications. However, the leaching of copper and its adverse effect on the aquatic ecosystem remains an issue. Micron-sized copper(II) as copper carbonate, dispersed in water (microdispersed or micronized copper systems), were then developed [START_REF] Schultz | Recent patents and developments in biocidal wood protection systems for exterior applications[END_REF].

Another type of non-metallic water-borne preservative is borates (boronbased compounds), which have a long history as wood preservatives. The most common borate preservatives are boric acid, sodium octaborate, sodium tetraborate, sodium pentaborate, and disodium octaborate tetrahydrate (DOT or borax). They are colorless, odorless, not corrosive to metal fasteners, and have low mammalian toxicity. Because borates have insecticidal and fungicidal properties, they are efficient preservatives even when used alone [START_REF] Richardson | Wood preservation[END_REF]; however, they remain water-soluble in wood and readily leach out in soil/rainwater [START_REF] Schultz | A brief review of the past, present and future of wood preservation[END_REF]. While fixing boron may increase its leaching resistance, it may lock the boron, which leads to the loss of biological efficacy. Thus, the key to expanding borate use is to improve their permanence in wood while retaining sufficient mobility to maintain its biological activity [START_REF] Obanda | Reducing leaching of boron-based wood preservatives-a review of research[END_REF].

The third-generation biocides, which totally organic material derived from agrochemicals, include triazoles (e.g., tebuconazole or propiconazole), which are active against Basidiomycete fungi and exhibit leach resistance and good stability once formulated in wood, and the synthetic pyrethroids (e.g., permethrin) or the highly active neonicotinoids (e.g., imidacloprid or thiamethoxam) which exhibit good efficacy against insects [START_REF] Schultz | A brief review of the past, present and future of wood preservation[END_REF].

Trends in wood protection

Environmental, health, and safety concerns related to the use of active substances in conventional wood preservation have led to governmental regulation. For more than a decade, formulations such as creosote, pentachlorophenol (PCP), and copper chromium arsenate (CCA) have been severely restricted or banned due to their adverse effects on the environment and human health. At the European level, regulations such as the REACH (Registration, Evaluation, Authorization, and Restriction of Chemicals) Directive (EC 1907(EC /2006) also significantly contribute to reducing the environmental risks of current treatment products. Over the past two decades, the trend on wood protection has gradually shifted from traditional "wood preservation" to "wood protection," which is a more general concept based not only on the inherent characteristics of the material itself but also on its interaction with the environment, such as design, maintenance, exposure and risk of moisture [START_REF] Kutnik | European standards on durability and performance of wood and wood-based products-trends and challenges[END_REF].

Various efforts to develop alternative protection methods have also been made. One of them is the use of natural products [START_REF] Singh | A review on natural products as wood protectant[END_REF]. Another approach is improving the wood properties and durability through non-biocidal application, such as thermal and chemical modification of wood [START_REF] Gérardin | New alternatives for wood preservation based on thermal and chemical modification of wood-a review[END_REF].

The use of natural products

The development of environmentally friendly wood protection, especially those from natural materials, has been undertaken to find sustainable substitutes for hazardous substances in wood protection applications [START_REF] Singh | A review on natural products as wood protectant[END_REF][START_REF] González-Laredo | Wood preservation using natural products[END_REF]. This includes several different approaches, such as using naturally occurring hydrophobic agents (e.g., waxes, plant oils, and resins) for moisture control or the utilization of natural compounds with biocidal properties and fixing them into wood [START_REF] Broda | Natural compounds for wood protection against fungi-a review[END_REF]. Several natural compounds derived from plants and animals have been shown to be effective against wood-destroying organisms, such as plant extract [START_REF] Tascioglu | Antifungal properties of some plant extracts used as wood preservatives[END_REF], essential oils [START_REF] Kartal | E ffect of essential oil compounds and plant extracts on decay and termite resistance of wood[END_REF][START_REF] Pánek | Ten essential oils for beech wood protection-efficacy against wood-destroying fungi and moulds, and effect on wood discoloration[END_REF], tannin [START_REF] Hu | Tannincaprolactam and tannin-peg formulations as outdoor wood preservatives: biological properties[END_REF][START_REF] Tomak | The wood preservative potentials of valonia, chestnut, tara and sulphited oak tannins[END_REF], chitosan [START_REF] Hussain | Preparation of chitosan oligomers and characterization: their antifungal activities and decay resistance[END_REF], and propolis [START_REF] Woźniak | The possibility of propolis extract application in wood protection[END_REF].

The use of natural products for wood protection is not free of limitations. Retention of organic biocides in impregnated wood tissues and their susceptibility to biodegradation are two major problems. The application of many of these compounds is also hampered by the leachability of treated wood when exposed to water. Potential methods for overcoming their shortcomings and increasing their bioactivity already exist, such as co-impregnation with different polymers, cross-linking, metal chelating, or antioxidants [START_REF] Singh | A review on natural products as wood protectant[END_REF]. Co-impregnation with water repellents (such as resin acid) can be an effective way of keeping the biocide leached out from treated wood [START_REF] Panov | Study on some alkoxysilanesu s e df o rh ydrophobation and protection of wood against decay[END_REF].

Another question remains regarding their toxicity towards human and environment since many studies on natural products for wood protection mainly focus on efficacy and often did not provide the ecotoxicity test. Indeed, as stated by [START_REF] Vetter | Methodology to assess both the efficacy and ecotoxicology of preservative-treated and modified wood[END_REF], it is not easy to find a way of treating wood with sufficient efficacy while at the same time also provide an excellent ecotoxicological profile of the leachates. While adequate protection against wood degrading organisms should be achieved, the ecotoxicity evaluation of the wood leachates should be followed until both durability and ecotoxicity are within satisfactory limits.

Wood modification

The wood modification method can use chemical (chemical modification) or heat (thermal modification) to change the wood structure. Various wood modification methods have been well studied, such as acetylation, furfury-lation, and heat treatment. In the acetylation process, the reagent such as acetic anhydride reacts with wood polymers. The process results in the substitution of the wood hydroxyl groups by acetyl groups through esterification [START_REF] Mantanis | Chemical modification of wood by acetylation or furfurylation: A review of the present scaled-up technologies[END_REF]. The reaction of wood with acetic anhydride can be carried out with or without catalyst within temperature between 100 and 130 • C followed by a vacuum step to remove unreacted volatile reagent or acetic acid (by-product) [START_REF] Obataya | Potassium acetate-catalyzed acetylation of wood: extraordinarily rapid acetylation at 120 c[END_REF]. The acetylation process improved physical, mechanical, and biological material properties. Furfurylation treatment is the process based on in situ polymerization of furfuryl alcohol, a compound derived from furfural, which is obtained from the hydrolyzed biomass. The properties of the modified wood depend on the retention of grafted/polymerized poly-FA. Once polymerized, the toxicity of furfuryl alcohol is significantly reduced [START_REF] Gérardin | New alternatives for wood preservation based on thermal and chemical modification of wood-a review[END_REF]. At high retention (high modification levels), some wood properties such as dimensional stability, hardness, MOR, MOE, resistance to decay, and insect attacks were improved [START_REF] Lande | Properties of furfurylated wood[END_REF].

Heat treatment or thermal wood modification is typically performed at temperatures between 180 • C and 260 • C [START_REF] Hill | Wood modification: chemical, thermal and other processes[END_REF]. Various process conditions can differ, such as the presence of a shielding gas (nitrogen, oxygen, water steam) or the use of oil (rapeseed oil, linseed oil, or sunflower oil) as treating media [START_REF] Lee | Thermal treatment of wood using vegetable oils: A review[END_REF]. Several chemical reactions occur during the treatment, considerably modifying the wood structure and improving the wood properties. The partial degradation of the hemicellulose components and cellulose and lignin, to some extent, causes a decrease in wood hygroscopicity, converting the hydrophilic nature of wood to become hydrophobic. Heat treatment improves the dimensional stability, lowers the equilibrium moisture content, and increase resistance against wood-decaying fungi (except in contact with soil). However, it has little effect on termites and caused degradation of mechanical properties [START_REF] Esteves | Wood modification by heat treatment: A review[END_REF].

Both chemical and thermal modification of wood have worldwide industrial application, such as Plato and Thermowood for heat treatment; and Accoya and Kebony for chemical modification. Moreover, until today, chemical modification research is very active, such as wood modification with succinic acid [START_REF] L'hostis | Beech wood treated with polyglycerol succinate: a new effective method for its protection and stabilization[END_REF], citric acid [START_REF] Mubarok | Beech wood modification based on in situ esterification with sorbitol and citric acid[END_REF], and lactic acid [START_REF] Grosse | Optimizing chemical wood modification with oligomeric lactic acid by screening of processing conditions[END_REF].

Conclusion

Despite its various qualities, some wood species have limited end-use due to their susceptibility to biological attack. Several studies have been carried out on different protection methods aiming to improve the wood's service life. In this section, the various type of biological agents that attack wood and the importance of wood protection have been discussed. As we are interested in investigating the potential of pyrolysis liquid for wood protection, the following section covers the literature review of previous work related to the topic.

Pyrolysis Liquid for Wood Protection

Potential of Pyrolysis Liquid

Potential of Pyrolysis Liquid

The utilization of pyrolysis liquid is already of interest in many areas such as biocide, insecticide, fungicide, plant growth stimulator, and source of valuable chemicals [START_REF] Tiilikkala | Future energy transitions for bagasse cogeneration: Lessons from multi-level and policy innovations in mauritius[END_REF][START_REF] Mathew | Pyroligneous acid-the smoky acidic liquid from plant biomass[END_REF][START_REF] Pimenta | Chemical composition of pyroligneous acid obtained from eucalyptus gg100 clone[END_REF]. A high concentration of acetic acid and furfural make pyrolysis liquid a potent natural pesticide. Due to its large composition of bioactive chemicals, such as organic acids, phenols, ketones, aldehydes, furans, and guaiacols, pyrolysis liquid was presumed to protect the wood against fungi and termite (Temiz et al., 2013a).

In this section, the potential of pyrolysis liquid related toitsutilizationas biocides and its application for wood treatment is presented. A brief history on the utilization of pyrolysis liquid both from slow and fast pyrolysis is also discussed.

History and utilization of pyrolysis liquid

Pyrolysis has been practiced by the Egyptians, Greeks, and Romans for producing charcoal from carbonization of wood, and collected the condensable volatiles for embalming purposes and for filling joints in wooden ships [START_REF] Tiilikkala | Future energy transitions for bagasse cogeneration: Lessons from multi-level and policy innovations in mauritius[END_REF]. Other than slow pyrolysis or carbonization, destructive distillation and dry distillation are similar terms used to describe this thermal process.

In the past, pyrolysis is also known as a technology for "distilling wood." In 1850, wood distillation was widely practiced on a commercial scale by heating wood in a closed retort [START_REF] Pecha | Pyrolysis of lignocellulosic biomass: oil, char, and gas[END_REF]. The condensed vapor was collected to give tar and aqueous layer (pyroligneous acid). Firstly, this liquor needs to be settled to separate the tar (soluble tar or settled tar) from the aqueous layer (Fig. 2.3). The settled tar phase can be distilled to produce pitch and other volatiles. Pitch is considered more solid than tar and was used for waterproofing and adhesives purposes if the biomass was softwood. On the other hand, the hardwood pitch was used as fuel because it had a lower value [START_REF] Diebold | A review of the toxicity of biomass pyrolysis liquids formed at low temperatures[END_REF]. Pyroligneous acid was obtained by decanted the liquor from tar sedimentation and is the primary source for acetic acid, methanol, and acetone. During that period, wood was the only source for those chemicals [START_REF] Tiilikkala | Future energy transitions for bagasse cogeneration: Lessons from multi-level and policy innovations in mauritius[END_REF].

From the 1920s to the 1950s, the wood distillation market was replaced by the petroleum industry [START_REF] Pecha | Pyrolysis of lignocellulosic biomass: oil, char, and gas[END_REF]. Currently, chemical production from wood distillation is rarely economically attractive in the Western Hemisphere. Wood carbonization is still practiced worldwide for heating, cooking, and industrial purposes, while chemicals are occasionally

Carbonization and traditional use of pyroligneous acid

It is known that the traditional farmers in some Asian countries have benefited from the pyroligneous acid as a by-product of the charcoal-making process (Fig. 2.4). In fact, pyroligneous acid has been used notably for agriculture purposes since the 1930s. Pyroligneous acid was used as alternatives to chemicals for improving crop yields (e.g., as a fertilizer and plant growth stimulant) and controlling pests (bio-pesticide). Currently, pyroligneous acid is also commercially available, such as in China, Japan, Thailand, Indonesia, and Malaysia.

In traditional charcoal production, woody biomass has been generally preferred feedstock. Therefore, pyroligneous acid often refers to wood vinegar. Wood vinegar is produced when smoke from charcoal production is cooled by the outside air as it passes through the chimney or flue pipe. The temperature of smoke ranges between 80 and 180 • C. A long hollow green bamboo pole is usually used to collect the condensable smoke by connecting it to the flue pipe (elevated to 40 • ). The bamboo pipe is only attached Figure 2.4: Traditional charcoal making process (left) and its by-product from the condensation of smoke (right) [START_REF] Kishimoto | Wood vinegar and biochar in agriculture[END_REF] when the smoke turns yellowish and acrid. A very thick and white smoke before that should be avoided due to the high moisture content. The bamboo is wrapped with damp cloths to help to give the cooling effect. One to two holes were made underneath the bamboo, 30 cm from the connection with the flue pipe. These holes will be the exit for the raw wood vinegar that can be collected using containers tied up underneath theb a m booh o l e s [START_REF] Burnette | An introduction to wood vinegar[END_REF]. When the droplets turn black, which indicates that tar has formed, the process is stopped. At this stage, the decomposition of char becomes very active, resulting in a stickier tar, and the smoke emitted during high temperature can also contain substances that are harmful to humans. The temperature of carbonization is usually kept under 425 • C to avoid these hazardous compounds (PAHs) [START_REF] Kishimoto | Wood vinegar and biochar in agriculture[END_REF].

Raw wood vinegar can be purified by a simple standing method by sealing it inside a tight container and let sit until 3-6 months in the ambient temperature. The three layers will be formed, with wood vinegar in the middle layer having a yellow to reddish-brown. The wood vinegar will separate itself from the sedimented tar which forms at the bottom. On top of wood vinegar, a light oily liquid is formed and will have a skim of wood tar. Wood vinegar is usually diluted in water in ratios between 1:50 (1 liter wood vinegar and 50 liters water) to 1:800 before use [START_REF] Burnette | An introduction to wood vinegar[END_REF].

Development of fast pyrolysis as a method to produce biooil

Until 1960, slow pyrolysis was the only technologically available method. At that period, fundamentals research on biomass pyrolysis reactions was studied, and researchers found that more liquid can be recovered when heating the feedstock very fast using small particles. Such technology refers to the fast pyrolysis method. Following the oil crisis in the 1970s, researchers develop reactors and conversion methods of chemical products from bio-oil until the 1990s. Until now, the research on pyrolysis focuses on the development of bio-oil upgrading (for the production of renewable fuels and chemicals) and the production of carbonaceous products (Pecha and Garcia-Perez, 2020).

Biological activity of pyrolysis liquid against fungi and termites

Tab. 2.3 and Tab. 2.4 summarize the biological activity of various pyrolysis liquid against rot-fungi and termites in laboratory bioassays. Most of the work found in the literature was using liquid from slow pyrolysis of various biomass. Among many type of wood-decaying fungi, pyrolysis liquid hasb e e n showed to have activity against white-rot (Trametes versicolor, Rigidoporopsis amylospora and Pleurotus ostreatus) and brown-rot (Coniophora puteana, Rhodonia placenta, Gloeophyllum trabeum, Fomitopsis palustris, Lentinus lepideus, and Tyromyces palustris). Termites such as Coptotermes formosanus and Reticulitermes speratus have also tested in previous experiments using liquid product from pyrolysis. Based on the literature review, the active concentration for termites is higher than that of fungi.

The anti-fungal and anti-termite properties of pyrolysis liquid depend significantly on its composition, which is influenced by the raw material and processing conditions. For example, [START_REF] Barbero-López | Pyrolysis distillates from tree bark and fibre hemp inhibit the growth of wooddecaying fungi[END_REF] tested different distillates using a range of pyrolysis temperature. They found that the liquid products from slow pyrolysis show higher fungal activity than torrefactionproduced liquid. Torrefaction, a low-temperature pyrolysis process (between 225 • C and 300 • C), usually produces a liquid with lower organic compounds, mainly organic acid and water. [START_REF] Theapparat | Pyroligneous acids from carbonisation of wood and bamboo: their components and antifungal activity[END_REF] used several type of biomass such as Eucalyptus camaldulensis, Leucaena leucocephala, Azadirachta indica, Hevea brasiliensis (rubberwood) and Dendrocalamus asper (bamboo) to produce pyroligneous acid from carbonization along with two commercial products. Before use, the samples were stored at room temperature in a closed container for at least 6 months to separate the heavy tar. They found that the liquid product from the pyrolysis of bamboo and rubberwood exhibited higher antifungal activity, due to the higher total phenolic concentrations, notably higher for 2-methoxy-4-propylphenol and 2-methylphenol. [START_REF] Oramahi | Antifungal and antitermitic activities of wood vinegar from oil palm trunk[END_REF] found pyrolysis liquid from oil palm trunk produced at 350 • C showed higher anti-fungal and anti-termites activity than those of liquid produced at 400 and 450 • C due to the higher acid and phenolic compound. [START_REF] Oramahi | Antifungal and antitermitic activities of wood vinegar from vitex pubescens vahl[END_REF] also highlighted the termiticidal activity and repellent effect of wood vinegar produced from Vitex pubescens to both R. speratus and C. formosanus workers. [START_REF] Kartal | Efficacy of tar oil recovered during slow pyrolysis of macadamia nut shells[END_REF] reported that tar oil recovered from the slow pyrolysis of macadamia nutshell was effective in inhibiting the growth of different rot fungi and sapstain fungus (Ophiostoma piliferum). At dilution 1:5000 (tar oil:growth medium), total inhibition was observed for white-rot P. ostreatus and T. versicolor. Higher concentration is required to completely inhibit the brown-rot fungi T. palustris and L. lepideus (1:500).

The biological activity of pyrolysis liquid against fungi and termites is often associated with the synergistic action of various compounds, instead of one molecule individually. The number of organic components of the pyrolysis liquid usually can be detected by GC-MS. However, single analytical method is inaccessible to thoroughly characterize the chemical species, so it requires the combination of more than one analytical methods [START_REF] Garcia-Perez | Characterization of bio-oils in chemical families[END_REF]. GC-MS is usually employed for the identification of volatile compound, whereas the non-volatile compounds can be detected by HPLC and HPLC/electrospray MS. Other analytical methods include Fourier transform infrared (FTIR) spectroscopy for identifying the functional groups, gel permeation spectroscopy (GPC) for the molecular weight distributions, and nuclear magnetic resonance (NMR) for the types of hydrogens or carbons in specific structural groups, bonds, and area integrations [START_REF] Mohan | Pyrolysis of wood/biomass for bio-oil: a critical review[END_REF].

Phenolic derivatives and organic acids (mainly acetic acid) is reported behind the fungicidal and insecticidal properties of pyrolysis liquid. The phenolic compounds such as 2-methoxy-4-methylphenol, 2,6-dimethoxyphenol (syringol), 2-methoxyphenol (guaiacol), 4-ethyl-2-methoxyphenol were frequently found as major constituents in pyrolytic fractions with antifungal effects. However, for the insecticidal activity, few studies have made the chemical analysis of active fractions, thus little is known about the interaction between the bio-oil constituents and the effects their effect on the insecticidal activity [START_REF] Mattos | Biocidal applications trends of bio-oils from pyrolysis: Characterization of several conditions and biomass, a review[END_REF].

Pyrolysis liquid treatments for wood protection

The potential of pyrolysis liquid for wood protection has been studied by previous researchers using various type of biomass and pyrolysis process (Tab. 2.5). Methods are varied regarding the liquid recovery (e.g., through fractination, liquid-liquid extraction, or using the whole liquid as obtained from the pyrolysis process). Before applying it to wood, some concentration can be performed using dilution in solvent such as ethanol or methanol. 2010) pyrolyzed scots pine (Pinus sylvestris L.) wood at 550 and 600 • C, and fractionated the liquid obtained into two parts (heavy and light fraction), using a glass separation funnel based on the color differences, while the liquid obtained at 450 • C was homogeneous with no visible fractions. They reported that the mass loss of treated samples against brown rot R. placenta was 7-10%, where no significant differences observed between the light and heavy fractions samples. The retentions of the impregnated samples varied between 306 to 823 kg/m 3 . [START_REF] Kartal | Efficacy of tar oil recovered during slow pyrolysis of macadamia nut shells[END_REF] utilize the term of tar oil to describe the dark brown oily liquid from slow pyrolysis of macadamia nutshell. They found that the tar oil (retention of 460 kg/m 3 ) protected wood well against the fungi and termites even after leaching. Their results showed that the mass losses in leached specimens were less than those observed in unleached specimens. [START_REF] Theapparat | Pyroligneous acids from carbonisation of wood and bamboo: their components and antifungal activity[END_REF] tested the antifungal effect of several pyroligneous acid from the carbonization of different wood and bamboo on the soil block experiments. They found all pyroligneous acid were moderately resistant or non-resistant to white-rot, brown-rot, and sapstain fungi with retention of 17.62 to 35.88 kg/m 3 . They also stated that the antifungal activities Pyrolysis Liquid for Wood Protection 2.2. Potential of Pyrolysis Liquid of all samples tested were higher against brown rot fungus (G. trabeum) than the two white rot fungi (T. versicolor and R. amylospora). [START_REF] Mohan | Fungicidal values of bio-oils and their lignin-rich fractions obtained from wood/bark fast pyrolysis[END_REF] fractionated different types of bio-oil from wood and bark of pine and oak that were generated at different pyrolysis temperatures and residence times to obtain lignin-rich fractions which consist mainly of phenols and neutrals. They reported that the lignin-rich fractions showed greater fungal activity than whole bio-oils for a impregnation solution at 10% concentration level (effective concentration for whole bio-oil was 25%), however the activity is lost after leaching. For the whole bio-oil, the results showed that the toxic fungicide threshold was between 96 and 192 kg/m 3 . [START_REF] Kim | Evaluation of the antifungal effects of bio-oil prepared with lignocellulosic biomass using fast pyrolysis technology[END_REF] used the pyrolysis liquid from the fast pyrolysis (500 • C and residence time of 1.9 s) of yellow poplar (Liriodendron tulipifera) sawdust. They found that pyrolysis liquid at 100% (retention = 214 kg/m 3 and 117 kg/m 3 ) or 75% (retention = 149 kg/m 3 and 27 kg/m 3 ) concentrations showed good decay resistance against wood-rot fungi T.palustris and T.versicolor. They also observed the agglomeration of product in the internal part of the wood which can be associated with the antifungal effect. [START_REF] Lourençon | Bio-oil from a fast pyrolysis pilot plant as antifungal and hydrophobic agent for wood preservation[END_REF] studied the bio-oil derived from fast pyrolysis of residual eucalypt wood fines at a concentration 10%, 50% and 100% against white-rot T. versicolor and brown-rot G. trabeum. Before application to wood, the bio-oil was heated at 80 • C to decrease its viscosity. They reported the bio-oil impregnated pinewood with high loading (57.44% and 81.30%) caused the complete mortality of the whole fungal colony in the first days of test. The authors also proposed the potential of bio-oil as an efficient hydrophobic agent as it is proved to decrease the water absorption and wettability of the treated pine wood. When wood is impregnated with bio-oil, it agglomerates and coats the surface of the wood's vascular microstructure, thus blocking the water flow inside the wood.

Pyrolysis liquid from fast prolysis

Combination with other compounds

Previous studies have been highlighted the limitation of pyrolysis liquid due its leachability. However, only few study conducted the analyses the chemical composition from the leachate products. [START_REF] Temiz | Efficiency of bio-oil against wood destroying organisms[END_REF] reported that a significant amount of phenolic compounds were leached, however detailed chemical analysis was not performed. [START_REF] Temiz | Effect of bio-oil and epoxidized linseed oil on physical, mechanical, and biological properties of treated wood[END_REF] employed epoxidized linseed oil (ELO) as potential hardener to decrease the bio-oil leaching and increase the wood's hydrophobicity. Their results suggested that ELO treatment significantly decreased the water uptake which confirmed by the water absorption test. However, the second impregnation with ELO slightly increased the mass loss caused by decay fungi. Nonetheles, the decay resistance of treated wood samples with 20% of bio-oil against brown (C. puteana) and white rot fungi (T. versicolor ) was very effective (less than 3% mass loss with retention of 50-100 kg/m 3 ).

Some studies also reported that bio-oils may be very effective as additives to biocide formulations or co-impregnation with pentachlorophenol, creosote, organic biocides and boron compounds for synergistically enhanced activity [START_REF] Cooper | Potential wood preservatives from wood-based pyrolysis oil[END_REF][START_REF] Mohan | Pyrolysis of wood/biomass for bio-oil: a critical review[END_REF]. [START_REF] Cooper | Potential wood preservatives from wood-based pyrolysis oil[END_REF] combined bio-oil with three different biocides (disodium octaborate tetrahydrate, tebuconazole and copper sulfate). Their results suggested that treating solutions combining 25% of bio-oil with tebuconazole or copper sulfate fungicides may have potential as wood preservatives.

Conclusion

In this chapter, particularly in section 2.2, it has been presented that pyrolysis liquid from different types of biomass can be used for wood protection due to its bioactive chemicals that have activity against various types of biological agents such as fungi and termites. However, those liquid products produced from either slow and fast pyrolysis can vary in terms of their effectiveness and chemical composition depending on the processing temperature and feedstock used.

Sugarcane bagasse is a raw material available in many southern countries and provides its potential for energetic valorization. As presented, in many developing countries, slow pyrolysis is practiced to get interesting char, and pyrolysis liquid as its by-product to be used for different purposes. In the next chapter, we will demonstrate our research findings on the valorization of sugarcane bagasse through slow pyrolysis for co-producing char and pyrolysis liquid. In the end, the use and efficacy of pyrolysis liquid to treat non-durable wood is investigated to evaluate the possibility and potential of this product for wood protection treatment.

Part II

Energetic valorization of sugarcane bagasse via slow pyrolysis

Introduction

This part presents the experimental study on the slow pyrolysis of sugarcane bagasse. As previously mentioned, the potential of lignocellulosic biomass for energy production can be advanced through biomass conversion by means of pyrolysis. Slow pyrolysis, which occurs at a low heating rate and long vapor residence time, yields a good quality of char [START_REF] Bridgwater | Renewable fuels and chemicals by thermal processing of biomass[END_REF]. This technique is attractive in converting the unstable biomass, which contains higher volatile matter, such as sugarcane bagasse, to a stable energy-rich product. Also, an interesting balance of char and liquid production can be obtained using this process. Since slow pyrolysis favors the production of char as the main target, we employed several parameters based on the previous studies. Past studies have reported that slow pyrolysis of sugarcane bagasse is optimum to produce the highest char yield at a heating rate range of 2 • C/min to 16 • C/min and at a temperature above 240 • C, where significant differences of mass loss occurred at a temperature between 300 • C to 500 • C [START_REF] Katyal | Carbonisation of bagasse in a fixed bed reactor: influence of process variables on char yield and characteristics[END_REF][START_REF] Carrier | Comparison of slow and vacuum pyrolysis of sugar cane bagasse[END_REF]. In addition, the optimal pyrolysis temperature for the maximum yield of solid and liquid products has been reported in the range of 400 • C-550 • C [START_REF] Kan | Lignocellulosic biomass pyrolysis: A review of product properties and effects of pyrolysis parameters[END_REF]. From those results, we could establish the slow pyrolysis experiments at a lower heating rate (1 • C/min and 10 • C/min) and intermediate temperature (400 • C and 500 • C).

The objective of this work is to evaluate the potential of sugarcane bagasse valorization via slow pyrolysis to co-produce char and pyrolysis liquid. The char resulting from different pyrolysis settings was assessed according to its yield and thermal properties, including the proximate, ultimate, and calorific analysis for evaluating its potential as an energy source. The liquid product was recovered by condensing the pyrolysis vapor and was subsequently used as a candidate for wood protection agents. The chemical composition of pyrolysis liquids selected from the process was also investigated. The bagasse has a moisture content of 8.48 % and was provided as a grounded form with a particle size of <2mm. Prior to the pyrolysis process, the samples were oven-dried at 105 • C for two hours to remove its moisture content (<1%). Samples of 100 g were used for each pyrolysis experiment.

Chapter 4

Materials and Methods

Slow pyrolysis of sugarcane bagasse

Reactor set-up and parameters

A bench-scale fixed bed reactor equipped with a set of condensation system was used for the slow pyrolysis experiments (Fig. 4.2). This device was placed in a muffle furnace oven, which generates heat to the reactor. The reactor vessel has a cylinder form with a diameter of 24 cm and a height of 20 cm. The reactor cap has a 59.5cm long connecting pipe, which allows smoke to exit the oven towards the condensation system. The condenser was circulated with the ice-cooled liquid, a mixture of water and ethylene glycol contained in the cooling bath. The condenser's temperature was held at the temperature of -15 • C at the beginning of the pyrolysis experiments. The experiments were carried out at a temperature of 400 • C and 500 • C, a heating rate of 1 • C/min and 10 • C/min, and holding time of 30 min and 60 min, resulting in eight pyrolysis treatments in total. In order to ensure the expected pyrolysis parameters, two thermocouples were set up inside the reactor to monitor and record the evolution of temperature as a function of time using the Data Control software. One thermocouple is placed in direct contact with the biomass, while another was located in the middle of the reactor (see Fig. 4.2). The constant flow of inert gas (N 2 ) was applied at a rate of 1L/min. The nitrogen flow removed the organic vapors and gas products from the reactor. Further, the pyrolysis vapors were cooled down in a single-stage consisting of a double tube condenser, which is maintained at a temperature between 0 and 5 • C and an electrostatic precipitator. A bottle filled with silica gel was set up at the end of the condenser system, and the mass of the light-end compounds trapped here was used for mass balance purposes only. The pyrolysis liquid (Fig. 4.3) was then collected from the round flask and then stored in a refrigerator at 5 • C before further use. The percent yield of char (CY) and pyrolysis liquid (LY) was calculated based on the ratio between the final products' weight to biomass's initial weight (Eq. 4.1 and Eq. 4.2). The gas yield can be calculated as difference; however it was not recovered and analyzed in this study. Each pyrolysis experiment was repeated three times.

CY (%) = m char m initial biomass × 100 (4.1) LY (%) = m liquid m initial biomass × 100 (4.2)
4.2 Characterization of biomass and char

Proximate analysis of biomass and char

The proximate analysis was conducted to evaluate the moisture, volatile matter, fixed carbon, and ash content of bagasse and char.

The moisture content of bagasse (ISO 18134-3, 2015) and char (EN1860-2, 2005) was determined by heating the samples in a drying oven at 105 • C for 2h or until reaching a constant weight. For the ash content, the samples of bagasse and char was heated in a muffle furnace to 550 • C and 710 • C, respectively. Briefly, the samples of bagasse or char were put in the uncovered crucible. For bagasse, the sample was first heated from the ambient temperature to 250 • C for 60 min, then ramped up from 250 • C to 550 • C for 60 min, and maintained at that temperature until constant weight (or at minimum 2h) (ISO 18122, 2015). For char, the sample was first heated from the ambient temperature to 250 • C for 30 min, then ramped up from 250 • C to 550 • C for another 30 min, and finally ramped up again until (710 ± 10) • C for 30 min and held until constant weight (or at minimum 2h)( EN1860-2, 2005). The volatile matter was released from the sample by heating the bagasse (ISO 18123, 2015) or char (EN1860-2, 2005) in the covered crucibles inside a muffle furnace to 900 • C for 7min. Lastly, the fixed carbon was determined by difference.

Elemental analysis of biomass and char

The elemental analysis was carried out to determine the content of carbon (C), hydrogen (H), and nitrogen (N) of bagasse and char by using an elemental analyzer VariMACROcube according to ASTM D5373 (2016) and ISO 16948 (2015). Meanwhile, the oxygen content (O) was obtained by difference. Samples of approximately 100 mg of bagasse and 30 mg of char were used within each run. Phenylalanine (Sigma-Aldrich) was used as a standard reference. The O/C and H/C atomic ratios were then determined from the obtained weight percent and atomic weights of the corresponding elements.

Higher Heating Value (HHV)

The gross calorific value or the higher heating value (HHV) of bagasse and char was experimentally measured using a bomb calorimetric PARR 6200 (ISO 18125, 2017) and determined on its anhydrous basis (Eq. 4.3).

HHV (J/g) = 4.1855 × E cal × T × Q fuse × Q N m × 100 100 -MC (4.3)
where 4.1855 is the conversion factor (from Cal to J), m is the mass of the sample (g), E cal is the average value of the effective heat capacity of the calorimeter as determined during calibration tests, T is the corrected temperature increase, Q fuse is the energy input from the combustion of the firing wire (Cal), Q N is the energy input from the formation of nitric acid (from water in the liquid state, nitrogen, and oxygen in the gaseous state) (Cal), and MC is the moisture content of the sample (%).

Ash Recovery (AR)

The ash recovery quantifies the amount of ash stored within the solid biochar phase after slow pyrolysis. The ash recovery (AR) was calculated following the study conducted by [START_REF] Ghysels | Production and characterization of slow pyrolysis biochar from lignin-rich digested stillage from lignocellulosic ethanol production[END_REF] and determined from the ash content of bagasse (Ash bag ), the ash content of char (Ash char ), and the char yield (CY) (Eq. 4.4).

AR(%) =

Ash char Ash bagasse × CY (4.4)

Energy Yield (EY) and Energy Density (EY)

The energy yield and energy density were determined according to the study conducted by [START_REF] Yang | Thermal properties of biochars derived from waste biomass generated by agricultural and forestry sectors[END_REF]. The energy yield (EY) was expressed as the ratio of the heating value of char (HHV char ) and bagasse (HHV bagasse ) multiplied by the char yield (CY) (Eq. 4.5). For energy density (ED), the value was determined as the ratio of energy yield and char yield (Eq. 4.6). The water content of pyrolysis liquid was determined using a Karl Fisher volumetric titration (Mettler Toledo, Karl Fisher V20) following the standard test method of ASTM E203-08 (2008). The pH of pyrolysis liquid was also measured using a pH meter (Portames R ⃝ 911pH). Only pyrolysis liquid produced at a temperature of 400 • C and 500 • C, a heating rate of 10 • C/min, and a holding time of 60 min were analyzed.

EY

FTIR analysis of pyrolysis liquid

Fourier transform infrared spectroscopy (FTIR) spectra of the pyrolysis liquid were recorded using a Perkin Elmer Frontier spectrometer equipped with an Attenuated Total Reflection (ATR) illustrated in Fig. 4.4. FTIR spectra were obtained at a nominal resolution of 4cm -1 for 4 scans in the range of 4000-650 cm -1 . The spectra were treated using RStudio using the package of MALDIquantForeign [START_REF] Gibb | Maldiquant: a versatile r package for the analysis of mass spectrometry data[END_REF][START_REF] Core | R: A Language and Environment for Statistical Computing[END_REF].

GC-MS analysis

Gas chromatography-mass spectrometry (GC-MS) analysis of pyrolysis liquid was performed using an Agilent 6890N gas chromatograph and Agilent 5975 mass spectrometer, all materials and chemicals being provided by Agilent. A 1ml of pyrolysis liquid sample was dissolved in 10 ml of analytical grade acetone and filtered with a nylon microfilter of 0.45 mm. Afterward, 1ml of sample volume was transferred into a glass vial followed byt h ei ntroduction of internal standards (acetic-acid-d4, toluene-d8, phenol-d6, and phenanthrene-d10). The gas chromatograph was equipped with an electronically controlled split/splitless injection port and a capillary column DB-1701. The injection (1 µl) was performed at 250 • C in the split mode (split = 1/10). Helium was used as carrier gas at constant flow (1.9ml/min). GC oven temperature was programmed to hold at 45 • C for 4min, then heated to 120 • C at a rate of 3 • C/min, and finally increased to 270 • C at a rate of 20 • C/min. The internal standard used for the quantification was acetic-acid-d4 and toluene-d8. For the splitless mode, the injection was performed at 250 • C. The oven temperature program was as follows: the initial temperature was set at 45 • C for 4min, then increased to 250 • C at a rate of 3 • C/min, increased again to 270 • C at a rate of 20 • C/min and held there for 60 min. Phenol-d6 and phenanthrene-d10 internal standards were used for the quantification of the compounds. The mass spectrometer was fixed at 70 eV ionization energy (ion source temperature = 230 • C). Detail apparatus specification can be found in study by Lê [START_REF] Lê Thành | Detailed identification and quantification of the condensable species released during torrefaction of lignocellulosic biomasses[END_REF]. In addition, a dilution to 1/10 (v/v) of a mixture sample in acetone was also performed to obtain the actual concentration of some calibrated compounds that were higher than the upper limit of the calibration range.

Data analysis

Multivariate regression analysis was conducted to determine each parameter's correlation and effects on the yield values and char properties. Temperature, heating rate, and holding time were the independent parameters. We then determined the significance of each of those parameters individually using p-value and globally by seeing their R 2 value.

Chapter 5

Results and Discussion

Characteristics of biomass

Tab. 5.1 summarizes the proximate, ultimate, and calorific analysis of the studied sugarcane bagasse and references from different studies. The proximate analysis provides information related to the burning quality of biomass [START_REF] Varma | Pyrolysis of sugarcane bagasse in semi batch reactor: Effects of process parameters on product yields and characterization of products[END_REF]. Sugarcane bagasse contains 8.5% of moisture content, 82.4% of volatile matter, 13.4% of fixed carbon, and relatively higher ash (4.2%) compared to other studies. The ash content of biomass tends to be higher when smaller particles were used [START_REF] Garcia-Perez | Sugarcane bagasse vacuum pyrolysis[END_REF][START_REF] Carrier | Comparison of slow and vacuum pyrolysis of sugar cane bagasse[END_REF]. Ash content has a detrimental effect as it is an inorganic, incombustible material that can lower the burning rate. The amount of ash content depends on the nature of biomass. As an illustration, rice straw has 14 % of ash content, while wood biomass such as birch wood has the lowest ash content, which is approximately 0.3% [START_REF] Yang | Thermal properties of biochars derived from waste biomass generated by agricultural and forestry sectors[END_REF]. Bagasse also contains a very low fuel ratio (fixed carbon/volatile matter) due to the high content of volatile matter. A fuel ratio of 1 or less is considered very low, while, as a comparison, the anthracite has a fuel ratio of 12 [START_REF] Chae | Combustion characteristics of solid refuse fuels from different waste sources[END_REF].

The ultimate analysis demonstrates the elemental composition of biomass. Sugarcane bagasse has 47.3%of carbon, 5.7%of hydrogen, 0.4%of nitrogen, and 46.7% of total oxygen and sulfur. The carbon and hydrogen contents are a good criterion for power generation and contribute most to the calorific value [START_REF] Pereira | Influence of chemical composition of eucalyptus wood on gravimetric yield and charcoal properties[END_REF]. The HHV of sugarcane bagasse was 18.1MJ/kg. It is one of the most important energy analysis parameters, defined as the released energy per unit mass or volume from the material after the complete combustion. In contrast, the presence of oxygen decreases the fuel's calorific value, while the low content of nitrogen and sulfur is imperative in terms of environmental aspects [START_REF] Demirbaş | Estimating the calorific values of lignocellulosic fuels[END_REF]. The analysis demonstrates that the present biomass is comparable to other sugarcane bagasse reported in different studies and possesses the potential as pyrolysis feedstock. [START_REF] Varma | Pyrolysis of sugarcane bagasse in semi batch reactor: Effects of process parameters on product yields and characterization of products[END_REF].

Effect of pyrolysis parameters on the product yields

The evolution of temperature as a function of time was monitored and corresponded well with the expected scheme (Fig. 5.1). The yield of char and pyrolysis liquid are presented in Tab. 5.2, followed by their coefficient of regression given in Tab. 5.3. The temperature was observed as the most important parameter, influencing the char yield (p-value = 5.37 × 10 -12 ) and liquid yield (p-value = 2.41 × 10 -5 ). The two heating rates (1 • C/min and 10 • C/min) also showed a significant effect on char yield (p-value = 5.33 × 10 -6 ) and liquid yield (p-value = 1.8 × 10 -5 ). Meanwhile, there is no significant difference in the product yields for the holding time of 30 min and 60 min.

Lower temperature promotes a higher char yield; however, it reduces the liquid yield and vice versa. The char yield was decreased from the temperature of 400 • C-500 • C as much as 12.65 % on average. [START_REF] Katyal | Carbonisation of bagasse in a fixed bed reactor: influence of process variables on char yield and characteristics[END_REF] stated that below 300 • C, the mass loss or the conversion of bagasse in slow pyrolysis is low and significant conversion occurs between 300 • C and 500 • C. The high yield of char at low temperature indicates that the biomass has only been partially pyrolysed. Further, they reported that the mass loss after 500 • C is negligible and the decrease of char yield was considered insignificant (3-4%) when pyrolysed between 500 • C-700 • C. In Tab. 5.2, the energy density of char was found higher (1.53-1.58) at higher pyrolysis temperatures, as the HHV also increases as the temperature increase. From all the conditions tested, the average of char and liquid yield varied between 28.81 %-35.12 %, and 49.67 %-55.46 %, separately. [START_REF] Aboulkas | Valorization of algal waste via pyrolysis in a fixed-bed reactor: Production and characterization of bio-oil and bio-char[END_REF] reported that pyrolysis liquid made from algal waste reaches a maximum yield at the temperature range of 500 • C-550 • C, while it decreases at the temperature of 600 • C. At higher temperatures, the secondary reaction is likely to occur and produce a significant amount of gas.

Results showed that the heating rate of 10 • C/min increased the liquid yield, but decreased the char yield. [START_REF] Katyal | Carbonisation of bagasse in a fixed bed reactor: influence of process variables on char yield and characteristics[END_REF] reported that the effect of heating rate on the char yield is more noticeable at temperatures lower than 400 • C. It conveys a negligible effect of the heating rate at a higher temperature when char production is the main target. The reduction of char yield at a higher heating rate has been explained as the result of the secondary cracking of the pyrolysis vapors and secondary decomposition of the char [START_REF] Carrier | Comparison of slow and vacuum pyrolysis of sugar cane bagasse[END_REF]. While preferring the high liquid yield, the higher heating rate should be chosen. However, at pyrolysis of 500 • C, [START_REF] Aboulkas | Valorization of algal waste via pyrolysis in a fixed-bed reactor: Production and characterization of bio-oil and bio-char[END_REF] reported no significant impact on the char or liquid yield using a higher heating rate (10 • C/min-50 • C/min). In our study, the highest liquid yield was observed at a temperature of 500 • C and a heating rate of 10 • C/min (55.46 %).

The decomposition of biomass during pyrolysis is associated with cellulose, hemicellulose, and lignin content. [START_REF] Varma | Pyrolysis of sugarcane bagasse in semi batch reactor: Effects of process parameters on product yields and characterization of products[END_REF] reported that sugarcane bagasse comprises 47.6% of cellulose, 39 % of hemicellulose, and a considerable low content of lignin (11.2%). According to [START_REF] Morais | Pyrolysis and combustion of sugarcane bagasse[END_REF], who investigated the thermal behavior of sugarcane bagasse, there are at least three critical stages in this process: (1) dehydration, (2) degradation of hemicellulose and cellulose, and (3) lignin decomposition. They investigated the maximum loss rate of hemicellulose was observed at 250 • C, cellulose at 330 • C, and lignin between 190 • C and 500 • C, with the maximum mass loss rate occurs at 430 • C. Hemicellulose and amorphous part of cellulose principally yield the condensable volatiles, whereas cellulose and lignin's degradation produces gases, tar, and char [START_REF] Katyal | Carbonisation of bagasse in a fixed bed reactor: influence of process variables on char yield and characteristics[END_REF].

Effect of pyrolysis parameters on the char properties

The proximate and ultimate analysis of bagasse char from different pyrolysis conditions are presented in Tab. 5.4, followed by their coefficient of regression illustrated in Tab. 5.5. Temperature and heating rate significantly influenced the content of volatile, ash, fixed carbon, elemental carbon, and HHV, while holding time contributes to the volatile matter content only. After being pyrolyzed, bagasse char has a volatile matter of 24.31 %-25.80 % at 400 • C, and 13.01 %-16.43 % at 500 • C. Previous studies confirmed that the volatile matter is affected by the pyrolysis temperature [START_REF] Katyal | Carbonisation of bagasse in a fixed bed reactor: influence of process variables on char yield and characteristics[END_REF][START_REF] Crombie | The effect of pyrolysis conditions on biochar stability as determined by three methods[END_REF], as the decrease of volatile matter follows the increase of temperature. The reduction of volatile content between the two temperatures occurs due to the cellulose and lignin decomposition. As the volatile released, fixed carbon and ash content percentage increased. The highest fixed carbon was observed at 68.50 %-73.01 %, while the ash content was found to be higher than 10 %. The ash content in the present study varied from 10.79 %-15.50 %; however, it is still lower than the study conducted by [START_REF] Varma | Pyrolysis of sugarcane bagasse in semi batch reactor: Effects of process parameters on product yields and characterization of products[END_REF], who found it to be 16.25 %. High ash recoveries presented in Tab. 5.4 also showed that ash is retained within the char and attractive for its application as soil amendments [START_REF] Ghysels | Production and characterization of slow pyrolysis biochar from lignin-rich digested stillage from lignocellulosic ethanol production[END_REF].

Higher temperature and lower heating rate also favor the higher carbon content and higher HHV. At 500 • C, lower heating rate resulted in higher carbon content (73.53 %-75.70 %) than those obtained at the higher heating rate (71.95 %-72.90 %). HHV produced from the sugarcane bagasse pyrolysis also increases from 18.14 MJ/kg to 28.67 MJ/kg at the higher temperature and lower heating rate. The char has a higher carbon content and a lower oxygen content compared to its raw material. The O/C and H/C molar ratio of char were lower than sugarcane bagasse due to the loss of H and O during pyrolysis. The O/C and H/C molar ratio of sugarcane bagasse was found as 0.74 and 1.43, respectively.

For energy application, low volatile content, low ash content, high fixed carbon, high carbon content, high H/C, low O/C, and high HHV should be preferred. Meanwhile, high ash recovery and high stable carbon contents (from fixed carbon) can be a good indicator of soil amendments. Generally speaking, bagasse char obtained at 500 • C, and a heating rate of 1 • C/min or 10 • C/min has met all the criteria. Indeed, a lower heating rate promotes higher char yield and higher HHV. However, in the present study, the HHV of char from the pyrolysis of 500 • C and the heating rate of 10 • C/min (27.85 MJ kg) is already higher or comparable to the HHV of char produced on the same temperature and heating rate < 10 • C/min by other studies [START_REF] Mesa-Perez | Unidimensional heat transfer analysis of elephant grass and sugar cane bagasse slow pyrolysis in a fixed bed reactor[END_REF][START_REF] Carrier | Comparison of slow and vacuum pyrolysis of sugar cane bagasse[END_REF]. [START_REF] Carrier | Comparison of slow and vacuum pyrolysis of sugar cane bagasse[END_REF] found that the optimum HHV of bagasse slow pyrolysis (27.67 MJ/kg) was obtained at T > 450 • C and a heating rate lower than 8 • C/min. As a heating rate of 10 • C/min also promotes higher pyrolysis liquid yield, it is reasonable to choose a higher temperature and higher heating rate in this study to coproduce the bagasse char and bagasse pyrolysis liquid. Since the temperature was a dominant factor influencing the char properties, char yield, and liquid yield, we evaluated the two types of pyrolysis liquid produced as a candidate for anti-fungal and anti-termite agents.

Characteristics of pyrolysis liquid

Pyrolysis liquid was obtained in a dark brown color with a pungent, smoky odor. Previously, [START_REF] Demirbas | The influence of temperature on the yields of compounds existing in bio-oils obtained from biomass samples via pyrolysis[END_REF] has stated that the pyrolysis liquid consisted of two distinct parts: an aqueous phase consisting of am i x t u r eo f light oxygenates; and tar, a non-aqueous phase containing insoluble organics of high molecular weight. At the time of the experiment, the liquid obtained was not entirely in a separated phase (the soluble tar was presented and mixed with the aqueous phase). The heavy tar was presented, and it can be separated from the aqueous phase by the decantation. However, not all the heavy tar was successfully recovered at the end of pyrolysis experiments. Some of them were trapped in the condensation system; however, this amount is not significant (1%). To avoid ambiguity, the term of pyrolysis liquid used in this study represents the total condensed liquid obtained from the pyrolysis experiments (crude pyrolysis liquid). Fig. 5.2 demonstrates the FTIR spectra, representing the functional group of the pyrolysis liquid. According to the spectra obtained, pyrolysis liquid was confirmed to have various chemical components, including oxygenated compounds, such as carboxylic acids, alcohols, phenols, aldehydes and ketones, and other chemical components such as alkanes, alkenes, and aromatics. The spectra of pyrolysis liquid obtained from the slow pyrolysis at the temperature of 400 • C and 500 • C were similar. The peak between 3400 cm -1 and 3200 cm -1 presents the O-H stretching vibration corresponding to alcohols and phenols' content. The weak peaks observed between 3000 cm -1 and 2800 cm -1 (C-H stretching) imply the presence of alkanes. The C=O stretching vibrations between 1780 cm -1 and 1650 cm -1 indicate the presence of ketones, aldehydes, and carboxylic acids [START_REF] Demiral | Production of biofuel from soft shell of pistachio (pistacia vera l.)[END_REF][START_REF] Islam | Properties of sugarcane waste-derived bio-oils obtained by fixed-bed fire-tube heating pyrolysis[END_REF]. Peaks at 1513 cm -1 (C=C stretching vibration) correspond to the presence of alkenes and aromatics. Peaks at around 1365 cm -1 signify the presence of alkane due to the C-H vibrations [START_REF] Temiz | Efficiency of bio-oil against wood destroying organisms[END_REF]. The region between 1300 cm -1 and 900 cm -1 (C-O stretching and O-H deformation vibration) was reported to correspond to the presence of alcohols, carboxylic acids, ethers, esters, and phenols, while for the region between 900 cm -1 and 700 cm -1 (C-H bending) corresponds to the existence of aromatic compounds. The spectra obtained were in accordance with the study carried out by [START_REF] Varma | Pyrolysis of sugarcane bagasse in semi batch reactor: Effects of process parameters on product yields and characterization of products[END_REF].

The main organic compounds present in the organic fraction of pyrolysis liquid are given in Tab. 5.6. Chemical analysis using a GC-MS allowed the quantification of 56 chemical compounds, where the total organic contents quantified were 29.63 % and 25.63 % for pyrolysis liquid produced at 400 • C and 500 • C, respectively. Indeed, the pyrolysis liquid contained some The chemical composition of the pyrolysis liquid is influenced by the content of cellulose, hemicellulose, and lignin in biomass. The holocellulose generated furans and carbohydrates, whereas the lignin led to the formation of phenolic compounds [START_REF] Demirbas | The influence of temperature on the yields of compounds existing in bio-oils obtained from biomass samples via pyrolysis[END_REF]. According to the analysis, pyrolysis liquid consisted of carboxylic acids, alcohols, aldehydes, ketones, furans, and anhydrosugars, whereas the acetic acid, glycolaldehyde, 1-hydroxy-2propanone, methanol, formic acid, and levoglucosan were the principal compounds. Excluding the water, acetic acid was the significant compound com- posing the pyrolysis liquid, presenting 7.22 %-8.48 % of the liquid. Sugarcane bagasse is reported to be high in the content of xylose (15.5%-28.9%)(Bezerra and Ragauskas, 2016), which contribute to the formation of acetic acid by the elimination of acetyl groups from the xylose unit [START_REF] Demirbas | The influence of temperature on the yields of compounds existing in bio-oils obtained from biomass samples via pyrolysis[END_REF]Temiz et al., 2013a). [START_REF] Demirbas | The influence of temperature on the yields of compounds existing in bio-oils obtained from biomass samples via pyrolysis[END_REF] studied the mechanism of the pyrolysis reaction of biomass. For example, methanol resulted from the methoxyl groups of uronic acid, whereas furfural came from xylose dehydration. Additionally, the degradation of xylan produced water, methanol, 1-hydroxy-2-propanone,1-hydroxy-2-butanone, 2-furfuraldehyde, acetic, propionic, and formic acid.

There is only a slight variation of the chemical compounds of pyrolysis liquid produced at the temperature 400 • C and 500 • C. However, higher or-ganic content was found for the pyrolysis liquid produced at 400 • C, which also possessed a higher content of furfural (1.19 %). An increase in pyrolysis temperature contributed to the increase of phenolic compounds and decrease to the organic acid content [START_REF] Kartal | Preliminary evaluation of fungicidal and termiticidal activities of filtrates from biomass slurry fuel production[END_REF]. Further, no polycyclic aromatic hydrocarbon compounds (PAHs) were found, or they were insignificant (less than 1 ppm). The PAHs content must be taken carefully into account because of their toxicity towards the environment and human health [START_REF] Guo | International perspectives: Sources, distribution, and toxicity of polycyclic aromatic hydrocarbons[END_REF]. In contrast to creosote, pyrolysis liquid presented in this study could be considered to be more environmentally advantageous. According to the European standard EN 13991 ( 2004) the maximum content of benzo(a)pyrene in creosote class B is 50 mg/kg. [START_REF] Cordella | Bio-oils from biomass slow pyrolysis: a chemical and toxicological screening[END_REF] stated that PAHs are formed with a higher proportion at a higher temperature (650 • C, 100 • C/min). Additionally, phenol formation increases as the continuous secondary degradation occur with the rising temperature [START_REF] Demirbas | The influence of temperature on the yields of compounds existing in bio-oils obtained from biomass samples via pyrolysis[END_REF].

Pyrolysis liquid has 42.34 ± 0.24 % and 42.30 ± 0.14 % of water content at 400 • C and 500 • C temperatures, respectively. Temiz et al. (2013a) reported that bio-oil made from giant cane has a water content of 34 %. Variation of water content is affected by the moisture content of biomass and dehydration reaction during pyrolysis. In addition, the condenser temperature, which is maintained at 0 • C during the pyrolysis process also likely to contribute to the high levels of water, acids, alcohol, and ketones [START_REF] Li | Pyrolysis of rice husk in a fluidized bed reactor: Evaluate the characteristics of fractional bio-oil and particulate emission of carbonaceous aerosol (ca)[END_REF]. The pH was recorded at 2, in which the acidic characteristic was due to the presence of the organic acid, aldehydes, and phenols [START_REF] Varma | Pyrolysis of sugarcane bagasse in semi batch reactor: Effects of process parameters on product yields and characterization of products[END_REF].

Chapter 6

Conclusion

Slow pyrolysis is an attractive method for converting the unstable biomass which contains high volatile matter, such as sugarcane bagasse, to a stable energy-rich product, even with limited yield but results in the favorable calorific value improvement. Moreover, the recovery of liquid products results in high mass yield. Pyrolysis temperature and heating rate had a significant influence on the char properties and the yield of char and pyrolysis liquid, where a high-quality char and high yield of pyrolysis liquid can be obtained at a temperature of 500 • C and a heating rate of 10 • C/min. The yield of char and pyrolysis liquid was 28.97 % and 55.46 %, respectively.

In this study, apart from its utilization for fuel due to the high carbon content (70.50 %) and HHV (27.85 MJ/kg), bagasse char is also potential to be used as soil amendments, as it has a high ash recovery (up to 98 %). For the pyrolysis liquid, water, acetic acid, glycolaldehyde, 1-hydroxy-2-propanone, methanol, formic acid, levoglucosan, furfural, followed by some phenol compounds and guaiacol derivatives, were found as the principal compounds. No polycyclic aromatic hydrocarbon compounds (PAHs) were found in the GC-MS analysis, or they were insignificant (less than 1 ppm). Due to its various chemicals, pyrolysis liquid seems to be potentially useful for wood protection agents.

Part III Pyrolysis liquid performances for wood protection

Introduction

This part presents the potential application of pyrolysis liquid for wood protection. As has been previously reported, the utilization of pyrolysis liquid is already of interest in many areas such as biocide, insecticide, fungicide, plant growth stimulant, and source of valuable chemicals [START_REF] Tiilikkala | Future energy transitions for bagasse cogeneration: Lessons from multi-level and policy innovations in mauritius[END_REF][START_REF] Pimenta | Chemical composition of pyroligneous acid obtained from eucalyptus gg100 clone[END_REF][START_REF] Mathew | Pyroligneous acid-the smoky acidic liquid from plant biomass[END_REF]. Due to its large composition of bioactive chemicals, such as organic acids, phenols, ketones, aldehydes, furans, and guaiacols, pyrolysis liquid was presumed to protect the wood against fungi and termite (Temiz et al., 2013a). [START_REF] Barbero-López | Pyrolysis distillates from tree bark and fibre hemp inhibit the growth of wooddecaying fungi[END_REF] reported that pyrolysis distillates from spruce bark, birch bark, and fiber hemp at 275 • C-350 • C temperatures provide inhibition to the growth of wood-decaying fungi. Pyrolysis liquid made from rubberwood and bamboo at 400 • C showed better anti-fungal activity towards white-rot, brown-rot, and sapstain fungi [START_REF] Theapparat | Pyroligneous acids from carbonisation of wood and bamboo: their components and antifungal activity[END_REF]. [START_REF] Oramahi | Antifungal and antitermitic activities of wood vinegar from oil palm trunk[END_REF] also studied the pyrolysis liquid from oil palm trunk at a 350 • C as an anti-termite.

In this study, we used the crude pyrolysis liquid as it is obtained from the pyrolysis experiments. Before applying it to wood, pyrolysis liquid was first tested to determine whether it has activity against fungi and termites in the Petri-dish tests. The pyrolysis liquid used in the screening test was obtained from the pyrolysis process at a 400 • C and 500 • C temperatures, 10 • C/min of heating rate, and holding time of 60 min. For the termite test, a quick method of measuring the remained paper area consumed by termites was developed. The paper area loss measurement was chosen instead of the evaluation based on weight loss, considering the pyrolysis liquid volatility. Besides, [START_REF] Grace | Measurement of termite (isoptera: Rhinotermitidae) feeding on paper by video image analysis[END_REF] stated that filter paper is susceptible to the mass changes caused by absorbing or releasing moisture from and towards its environment, thus can affect the accuracy of the measurement. Therefore, we developed an alternative and robust measurement method byc a l c u l a t i n g the paper's remaining area.

The wood treatment test was then continued by applying the pyrolysis liquid produced at a temperature of 500 • C, a heating rate of 10 • C/min,and a holding time of 60 min. As the preliminary test, we were interested in evaluating the effect of different drying temperatures on the treated samples, as reported in some previous studies (Tab. 7.1). The effect of leaching was Introduction also investigated, along with tests on chemical analysis and the effect of leachate products on fungal growth. Lastly, the samples after leaching were tested for their efficacy towards Reticulitermes flavipes termites. After determining the desirable drying temperatures for wood samples, the impregnation process was done using pyrolysis liquid at different concentrations. In this step, the efficacy and the threshold of the pyrolysis liquid's concentration towards decay fungi and termites were evaluated. The effect of leaching and evaporation were also investigated.

Chapter 8

Materials and Methods

Anti-fungal and anti-termite test

Fungal inhibition test

Pyrolysis liquid produced at a temperature of 400 • C and 500 • C, a heating rate of 10 • C/min, and a holding time of 60 min were tested for its antifungal activity. The fungal inhibition test was evaluated using two types of wood-decaying fungi: Coniophora puteana (brown-rot, strain BAM Ebw. 15) and Trametes versicolor (white-rot, strain CTB 863 A) in the maltagar medium. The medium was prepared by mixing 40 g of malt (Quaron) and 20 g of agar (Biomerieux) in 1L of deionized water (water quality 3) and sterilized using an autoclave at 121 • C for 20 min. To determine the Minimum Inhibitory Concentration (MIC), various concentration (v/v) of pyrolysis liquid (0.05 %, 0.10 %, 0.15 %, 0.20 %,a n d0.25 %) were tested by diluting them directly in the malt agar solution. Right after the malt agar solution (40 ml) was distributed into Petri-dishes (diameter of 9cm), the pyrolysis liquid solution was introduced using a micropipette. Afterward, the mixture was stirred until it homogenized and left until it solidified. Four replicates were used for each treatment. A mycelium piece from a growing fungal culture (diameter of 5mm) was placed centrally, and then the medium was incubated at (22 ± 2) • C and (70 ± 5) % relative humidity (RH). The inhibition rate (I r ) was determined by comparing the diameter of fungal growth on the treated medium with the control (Petri-dishes containing only malt-agar medium), following the method described by Kartal et al. (2011) (Eq. 8.1).

I r (%) = 1 - D t D c (8.1)
where D c is the colony diameter of mycelium from the control Petri-dishes (mm), and D t is the colony diameter (mm) of mycelium from tested the Petri-dishes containing the pyrolysis liquid. A 9-cm diameter of Petri dish was filled with approximately 30-40 g of the wet Fontainebleau sand (4 vol. of sand/1 vol. of deionized water. The Joseph papers were placed on the plastic mesh to avoid water saturation. The test device is illustrated in Fig. 8.1. Then, a total of 20 termite workers were introduced in each petri dish and put in a dark climatic chamber at 27 • C, RH >75 %, for 4 weeks, watered and observed regularly. The mortality rate of termites (M r ) (Eq. 8.2) and the paper area loss were determined. A quick method of measuring the remained paper area consumed by termites was developed and described further in the subsection 8.1.4.

M r (%) = n 20 × 100 (8.2)
where n is the number of dead termites, and 20 is the number of initial termites added in the test. The number of termites workers that made contact with paper were counted every 5min in a 60 min observation (n = 12 counts), following the experimental work described by [START_REF] Oramahi | Antifungal and antitermitic activities of wood vinegar from vitex pubescens vahl[END_REF]. The mortality of termites (Eq. 8.2) was also determined at the end of the test. Four replicates were performed for each treatment. Following the experimental work described in the subsection 8.1.2, the total remaining paper area consumed by termites were measured through k-means clustering method that was built into the Scikit-Learn, a machine learning package written in Python, an open-source general programming language (Van Rossum and Drake Jr, 1995; [START_REF] Pedregosa | Scikit-learn: Machine learning in python[END_REF]. This technique is one of the widely used clustering algorithms intended to distribute n objects into k number of clusters with a central point, also known as the mean, nearest to all of the other data in that cluster.

The principal algorithm of k-means clustering can be written as:

φ = Σ k j=1 Σ n i=1 ||x i (j) -c j || 2 (8.3)
where φ is the total of intra-cluster variance, which would become the objective function, k is the number of clusters requested, n is the number of data points, x i (j) is the data point i, assumed to be in one of the k clusters (thus, it is in cluster j), and c j is the centroid for cluster j, or the varied parameter of the function. The aim here is to minimize the φ value until the c j points do not have to be changed anymore.

The algorithm consisted of the following principal steps:

1. determine k number of initial centroids, possibly where min(x i ) <c j < max(x i ),

2. calculate the euclidean distance of each data point to both centroids. Assign each data points to the centroid closest to them, 3. calculate the true centroid of true mean of all objects in each cluster, 4. if the true mean of each cluster is not equal to the initially guessed centroids, use the new true mean as new centroids, and repeat the steps above using these new centroids, 5. do the steps 2-4 continuously until the new true centroids equal to the previous ones, which indicate that the convergence has been obtained.

The automated segmentation protocol and paper area measurement was outlined in Fig. 8.3 and described below. Firstly, we put the remaining filter paper, usually having the color white or grey, on a clean surface with color in contrast to the filter paper. Some possible surface or background color choices would be red, blue, green, or even black. In our example here, we used the color red. Then we took the pictures of the paper using a known and uniform scale. This would be the image acquisition step, and it would produce original images, mentioned in Fig. 8.3.

Next, we started the program by running it, similar to launching a Python script. The code was written in two versions: with GUI (graphical user interface), where the user will be presented with dialog windows asking, consecutively: (1) to select the repository or folder containing the original, acquired image, (2) to select the reference image, which means the filter paper photo which was not consumed by termite at all, (3) to select the folder where the classified images would be saved, and (4) the name of the output file, written in comma-separated values (CSV) format. A degree of flexibility could be experienced here. In the non-GUI version, the code will, by default, seek the following:

• folder containing acquired image: "Data/", with images having ".tif" extension,

• reference picture: image file named "ref.

tif",

• output folder to save the classified images with the name: "Output/"

• output CSV file named "Results.csv"

For the non-GUI version, the choices of name and extension fore a c ho f the parameters above are also modifiable, but manually by editing the .py script file.

At the start of program's running, the code would import the original image as a numpy array. This is possible by reading each pixel's color as the array's values and the x and y coordinates of each pixel as the row and column index numbers. The next step is checking if the picture is in black and white or not. If it is not yet in black and white, the maximum values of the array would be > 255, and in that condition, we divide the values of each pixel with 255 to lower the euclidean distances of each pixel. This would be useful to accelerate the algorithm.

Afterward, the segmentation would take place using k-means clustering method. Because the objective here was classifying the imagei n t ot w oc a t egories: the filter paper and the background, we put the value of k =2. Each pixel's colors would be categorized into one of those two, and in the end, each pixel's values would be replaced by the centroids of each category. The last step would be threshold operation, which would convert each pixel's value into white (0) for filter paper and black (1) for the background. Overall,

Memory analysis

The final step is the memory and time analysis of our code. To do this, we prepared the version of the program without the GUI and used it to do image processing on 3, 5, 7, 9, 11, 13, and 15 acquired images, consecutively. During each of our program's running process on these images,thecomputer memory used was recorded using mprof, a memory profiling package built-in Python. The memory was measured once per 0.1s. This would give us two parameters: the total running time (t tot ) of the program, the evolution of memory over time, and the maximum amount of memory (M max ) used by the program for each total number of the image (N image ).

The t tot and M max parameters were then compared towards the N image using simple linear regression analysis to see if there is any clear relationships between the three parameters. We hypothesized a linear relationship with the N image as the independent parameter, such as the normal condition for the image analysis program. This could give us a clear visualization and information on the amount of computer memory needed to use this program and the total number of images that could be acceptably processed at one time.

Wood treatment

Wood samples preparation

Conditioned portion (20 ± 2) • C and (65 ± 5) % of beech wood (Fagus sylvatica) and pine sapwood (Pinus sylvestris), were cut into a dimension of (2.5 × 1.5 × 0.5) cm (L × R × T). Prior to impregnation, the samples were oven-dried at 103 • C until they reached their constant mass.

Wood impregnation and drying procedures

Impregnation procedure

Oven-dried beech wood samples (six replicates per treatment) were impregnated with the crude pyrolysis liquid (without dilution) by a single vacuum pressure impregnation. In a beaker, wood samples, together with the pyrolysis liquid, were put into a desiccator. The samples were kept immersed during the treatment (30 mbar vacuum for 20 min, followed by 2h at ambient pressure). The samples were then removed and blotted with tissue paper to remove the excess of the product from the wood surface. The retention (R in kg m -3 ) and the impregnation rate (IR in %) of pyrolysis liquid after impregnation was determined with the following formula (Eq. 8.6 and Eq. 8.7):

R(kg m -3 )= M w -M o V (8.6) IR(%) = M w -M o M o × 100 (8.7)
where M w is the wet weight of samples after impregnation (kg), M o is the initial dry weight samples (anhydrous state) before impregnation (kg), and V is the volume of samples at conditioned state before impregnation (m 3 ). For all the following experiments, the same impregnation procedure was used.

Drying procedure and visual observation using a light microscope

Five different drying temperatures were tested:

20 • C, 40 • C, 60 • C, 80 • C,
and 103 • C. For ambient temperature, samples were dried for three weeks, for temperature 40 • C samples were dried for one week, and for temperature 60 • C, 80 • C, and 103 • C, samples were dried for 24 h. The weight of the samples after drying was then recorded to determine the weight percent gain (WPG in %) using the following equation (Eq. 8.8): (8.8) where M d refers to the dry weight of samples after treatment (g), and M o is the initial dry weight samples (anhydrous state) before treatment (g). Finally, all the samples were reconditioned at (22 ± 2) • C and (65 ± 5) % relative humidity (RH). The microstructure of treated wood samples was captured using a digital camera Nikon DS Fi1 connected to a light microscope (Olympus BX6) with 100 × enlargement.

WPG(%) = M d -M o M o × 100

Impregnation using different concentrations of pyrolysis liquid

For the rest of the impregnation test, the drying temperatureforthetreated samples was first determined based on the work described above. After obtaining the desirable drying temperature (103 • C), the treatment was continued by impregnating the samples of beech wood and pine wood using different concentration of pyrolysis liquid diluted in ethanol (5%, 10 %, 15 %, 20 %, 25 %, and 50 % (v/v)). The impregnation procedure remained the same, where twelve replicates were used for each treatment.

FTIR analysis of treated and untreated wood

The untreated and treated beech wood samples from each drying temperature were milled to form a fine and homogenous powder. All samples were then analyzed using a Perkin Elmer Frontier spectrometer equipped with an Attenuated Total Reflection (ATR), as previously described in the subsection 4.3.2. FTIR spectra were obtained at a nominal resolution of 4cm -1 for 4 scans in the range of 4000-650 cm -1 . The spectra were treated using RStudio using the package of MALDIquantForeign [START_REF] Gibb | Maldiquant: a versatile r package for the analysis of mass spectrometry data[END_REF][START_REF] Core | R: A Language and Environment for Statistical Computing[END_REF].

Leaching procedure

Leaching test

The leaching test (Fig. 8.5) was carried out according to the standard NF X 41-568 (2014). Half of the total samples that were impregnated from each treatment were subjected to six successive leaching periods(1h, 2h, 4h, and 8h, 16 h, and 48 h). The samples were put into a closed container where they were immersed in deionized water (1 vol of wood/5 vol of deionized water). In the first period, the samples were submitted to continuous stirring, and the water was changed/replaced after 1, 2, and 4h. Afterward, the samples were removed and kept at (20 ± 2) • C and (65 ± 5) % RH for 16 h. The leaching process was then continued to the next periods for 8, 16, and 48 h, with water replacement conducted between each period. Controls of untreated beech wood (six replicates) were also leached following the same steps. After all the leaching periods completed, all wood samples were re-dried according to their initial drying temperature (ambient, 40 • C, 60 • C, 80 • C, or 103 • C) until reaching their constant mass. The weight percent gain after leaching (WPGL in %) and the leaching rate (LR in %) were calculated using the following equations (Eq. 8.9 and 8.10):

WPGL(%) = M l -M o M o × 100 (8.9) LR(%) = M d -M l M d -M o × 100 (8.10)
where M l is the dry weight of samples after leaching (g), M o is the initial dry weight of samples (anhydrous state) before treatment (g), and M d is the dry

Water absorption

Using the same samples dried at different temperatures and their control specimens, the wet weight after each leaching cycle was recorded to obtain the result on the water absorption. This step is conducted to get an idea of pyrolysis liquid's hydrophobic properties as described by [START_REF] Lourençon | Bio-oil from a fast pyrolysis pilot plant as antifungal and hydrophobic agent for wood preservation[END_REF]. The water absorption (WA in %) was calculated according to Eq. 8.11.

WA(%) = W a -W b W b × 100 (8.11)
where W a is the wet weight of samples before water replacement (g), and W b is the wet weight of samples after water replacement (g) in every leaching period.

Evaporation test

Twelve samples of beech treated with 100% pyrolysis liquid and dried at 103 • C were used for the evaporation test. Specimens were subjectedt oa n air flow of 1m/s at 40 • C for a week. Afterward, the samples were oven-dried at 103 • C, and the percentage of weight loss after evaporation (WLE in %)

Materials and Methods

Analysis of the leachate products

was determined (Eq. 8.12). (8.12) where, M d is the dry weight of samples before evaporation (g), and M e is the dry weight of wood samples after evaporation (g).

WLE(%) = M d -M e M d × 100

Analysis of the leachate products

Chemical analysis of the leachate products using GC-MS

The leachate products from different samples after different drying temperatures were collected from the leaching process and analyzed using GC-MS. Detailed on the GC-MS procedure has previously described in subsection 4.3.3.

Fungal inhibition test using leachate products

A simple measurement was conducted to determine whether the leachate solution collected from different samples contains substantial active compounds to inhibit fungi. The malt-agar medium (4% malt, 2% agar) was prepared using the collected leachate products from every leaching process. The pH of leachate solution was previously adjusted to 7 by adding NaOH (Sigma-Aldrich) 1 M to allow the solidification of the medium. Two mycelium pieces from a growing fungal culture (diameter of 5mm) of brown-rot (Coniophora puteana, strain BAM Ebw. 15) and white-rot (Trametes versicolor, strain CTB 863 A) were placed on the right and left edge of the 9cm diameter of a petri dish. The medium was then incubated at (22 ± 2) • C and (70 ± 5) % relative humidity (RH). The malt-agar medium prepared in the distilled water was used as control. Four replicates were used for each treatment. The radial growth of mycelium was measured after eleven days of exposure.

Fungal resistance test and correction factor

Fungal resistance test

The fungal tests (Fig. 8.6) were conducted following a screening test method [START_REF] Grosse | Optimizing chemical wood modification with oligomeric lactic acid by screening of processing conditions[END_REF], derived from EN 113-1 (2020) using two types of wooddecaying fungi: a white-rot (Trametes versicolor, strain CTB 863 A), and Wood samples were sterilized in two cycles using an autoclavea t121 • C for 20 min and 10 min, respectively. Three of the treated samples from leaching or non-leaching treatment (six replicates per treatment) and one control (untreated sample) were placed in each culture flask. Virulence controls were also performed using twelve specimens of untreated beech and pine sapwood samples. Incubation was carried out at (22 ± 2) • C and (70 ± 5) % RH. After eight weeks of fungal exposure, the mycelium was carefully brushed and removed from the samples and weighed to evaluate their moisture content (MC in %) (Eq. 8.13). The specimens were finally dried at 103 • C, and the weight loss (WL in %) was determined (Eq. 8.14): (8.14) Materials and Methods

MC(%) = M b -M c M c × 100 (8.13) WL(%) = M a -M c M a × 100

Termites resistance test

where, M a is the dry weight of wood samples before being exposed to fungi (g), M b is the weight of wood samples after being exposed to fungi (before being dried) (g), and M c is the dry weight of wood samples after being exposed to fungi (g).

For the fungal test results, WL will be corrected with the correction factor as described in EN 113-1 (2020).

Fungal correction factor

The same treatment using the same procedure (six replicates per treatment) was conducted without the presence of fungi (only samples put in the maltagar medium) to determine the correction factor by evaluating the weight loss of the samples at the end of the test. This test was conducted to obtain the samples' weight loss caused by a non-fungal attack (caused by leaching in the culture flask).

Termites resistance test

Termite resistance test (Fig. 8.7) was evaluated according to a non-choice screening test [START_REF] Mubarok | Comparison of different treatments based on glycerol or polyglycerol additives to improve properties of thermally modified wood[END_REF], derived from the European standard EN 117 (2013). It is the same procedure as described for the filter paper test (see subsection 8. 1.2). Each wood sample before and after leaching (three replicates per treatment) was exposed to 50 workers of R. flavipes (ex. santonensis) termites in a Petri dish with 9cm of diameter. One nymph and one soldier were also introduced to each Petri dish. Three replicates of untreated beech wood were also set up, as termite virulence controls, following the same procedure. The Petri dishes were then put in a dark climatic chamber at T = 27 • C and RH >75 %. After four weeks, the samples were removed, cleaned, and dried according to their initial drying temperature until reaching their constant mass.

A visual rating, according to the EN 117 ( 2013), but adjusted to the sample size, was also given to each sample (Tab. 8.1). Finally, the termite survival rate was quantified, and the wood samples' weight loss (WL in %) were determined through the following equation (Eq. 8.15)

WL(%) = M a -M b M a × 100 (8.15)
where, M a is the dry weight of wood samples before being exposed to termites (g), and M b is the dry weight of wood samples after being exposed to termites (g).

Data analysis

A t-test analysis was used to compare the data from each specimen and treatment. The data were analyzed in order to see their groupings (the same groups are indicated by the same letter) at a significance level of p <0.05. The analysis was conducted using Microsoft Excel, R, and RStudio( R Core Team, 2019).

Chapter 9

Results and Discussion

9.1 Anti-fungal and anti-termites activity

Effect of pyrolysis liquid in inhibiting fungi

The two types of pyrolysis liquid (400 and 500 • C) revealed their efficacity to inhibit the growth of C. puteana and T. versicolor (Fig. 9.1) in the Petridish test. Fig. 9.2 shows the comparison of the fungal growth between the treated and untreated samples. Pyrolysis liquid produced at 400 • C slightly tends to be more active, delaying the fungal growth at lower concentration, likely because of the relatively higher organic contents. According to the GC-MS analysis (Tab. 5.6), pyrolysis liquid at 400 • C contains higher organic acid and furfural than the pyrolysis liquid obtained at 500 • C.A ta 0.15 % concentration, pyrolysis liquid at 400 • C caused a 100 % inhibition of C. puteana. Also, to inhibit the fungal growth completely, pyrolysis liquid at a concentration of 0.20 % and 0.25 % was required to suppress the growth of C. puteana and T. versicolor, respectively. The different effect of pyrolysis liquid towards the fungi was likely correlated to the different metabolic rates or the enzyme released by the fungi [START_REF] Barbero-López | Pyrolysis distillates from tree bark and fibre hemp inhibit the growth of wooddecaying fungi[END_REF]. It is not easy to compare the results with other studies since the high variability of pyrolysis liquid influenced by pyrolysis parameters and the nature of biomass used. However, mostly, at a concentration of less than 1%, pyrolysis liquid has an excellent inhibition activity against various types of wood-decaying fungi. [START_REF] Barbero-López | Pyrolysis distillates from tree bark and fibre hemp inhibit the growth of wooddecaying fungi[END_REF] found that the MIC values for the complete inhibition were between 0.5% and 1% by using the liquid product from the pyrolysis of tree bark and fiber hemp at the temperature of [START_REF] Kartal | Efficacy of tar oil recovered during slow pyrolysis of macadamia nut shells[END_REF] reported the tar oil made from the slow pyrolysis of macadamia nut shells effectively inhibited the brown-rot fungi, white-rot, and sap-staining fungi tested at the concentration of 0.20 %.

275 • C-350 • C. Meanwhile,
The anti-fungal activity of pyrolysis liquid was likely the results of the synergetic effect from the various chemical compounds. The inhibition can also occur probably because of the compounds affect the enzymatic activity of the fungi. Several authors have reported that propionic acid [START_REF] Barbero-López | Pyrolysis distillates from tree bark and fibre hemp inhibit the growth of wooddecaying fungi[END_REF], acetic acid [START_REF] Oramahi | Antifungal and antitermitic activities of wood vinegar from oil palm trunk[END_REF], and furfural (Pimenta 2019) reported that at the concentration of 0.1% or below, propionic acid alone could completely inhibit fungal growth such as C. puteana. Guaiacols derivatives, which were also found in this study, such as phenol-2-methyl, phenol-3-methyl, phenol-4-methyl, phenol-2-methoxy-4-methyl, and phenol-4-ethyl-2-methoxy were also responsible for the ability of pyrolysisl i q u i dt oi n h i b i t fungi [START_REF] Mourant | Anti-fungal properties of the pyroligneous liquors from the pyrolysis of softwood bark[END_REF][START_REF] Mohan | Fungicidal values of bio-oils and their lignin-rich fractions obtained from wood/bark fast pyrolysis[END_REF].

Effect of pyrolysis liquid in termite's non-choice test

The effect of pyrolysis liquid on the paper area loss and mortality of R. flavipes are presented in Fig. 9.3. Control paper samples treated with deionized water and ethanol represent the equal portion of paper area loss (76.22 % and 79.3%, respectively) with a low rate of mortality (8.33 % for both controls). Results show that paper treated with ethanol was proved not to affect the termites feeding activity. Fig. 9.4 shows the remaining paper area consumed by termites. At a 5% concentration, termites consumed less paper experimentation, termites seemed to stay away from the treated samples, probably because of the unpleasant odor from the pyrolysis liquid. It has been known that pyrolysis liquid has a smoky flavor characteristic due to the presence of ketones, phenol, guaiacol, and syringol [START_REF] Yasuhara | Volatile compounds in pyroligneous liquids from karamatsu and chishima-sasa[END_REF][START_REF] Mathew | Pyroligneous acid-the smoky acidic liquid from plant biomass[END_REF]. The volatile compounds released during the experimentation was believed to repel the termites as reported by [START_REF] Oramahi | Antifungal and antitermitic activities of wood vinegar from vitex pubescens vahl[END_REF]. However, since the results showed that some termites have to consume the treated paper to die, the repellency is not enough, and the ingestion is necessary to make the termite die. Pyrolysis liquid produced from the biomass pyrolysis has been reported to have activity against Reticulitermes speratus, Coptotermes formosanus, C. curvignathus, and Odontotermes sp. [START_REF] Mattos | Biocidal applications trends of bio-oils from pyrolysis: Characterization of several conditions and biomass, a review[END_REF]. The presence of formaldehyde in the pyrolysis liquid, akin to that of carbamate, can affect insects' nervous system [START_REF] Wititsiri | Production of wood vinegars from coconut shells and additional materials for control of termite workers, odontotermes sp. and striped mealy bugs, ferrisia virgata[END_REF]. Acetic acid and phenols also contribute to the termiticidal activity. [START_REF] Yatagai | C et H/C de la bagasse de canne à sucre était respectivement de 0,74e t1 , 4 3 . Le liquide de pyrolyse obtenu est de couleur brun foncé avec une odeur piquante et fumée[END_REF] stated that formic acid showed strong termiticidal activities against R. speratus.

Effect of pyrolysis liquid in termites' choice test

The termite's choice test was conducted to examine the repellency effect of pyrolysis liquid towards termites. The number of termites in contact with paper was recorded, and their average and median values were presented in Tab. 9.1. The control paper (paper treated with deionized water) showeda high termite's preference compared to the paper treated with pyrolysis liquid. Pyrolysis liquid is significantly repelling the termites from the paper, while only a small number of termites observed made contact with the corresponding samples. Pyrolysis liquid produced at 400 • C had a slightly high repellency than the one produced at 500 • C. However, statistically speaking, they do not differ significantly. At the lowest concentration tested in this study (5%), pyrolysis liquid had a repellent effect towards R. flavipes. Indeed, for the control treatment, termites were made an unequal contact with the paper (the two corresponding papers were treated in the same manner). During a 60 min test, termites tend to randomly choose the paper when they first introduced to the Petri-dishes, and they were observed to stay in the same place afterward. At the beginning of the test, we also hypothesized that the ethanol-treated paper would not give any significantd i fferences toward termite's preferences, as the results on the termite's non-choice test support our assumption. In this case, the data showed that termites were indeed made an equal contact in regard to the ethanol and control paper in all the treated medium (in the range of 12.35 to 13.89 termites). While it seems that termites tend to prefer ethanol-treated paper to the control paper, it is worth noting that the number of termites in contact with the control paper in the control and ethanol treatments was still in the same statistical group range (6.40 and 7.19, respectively). The standard deviation was also found high for the ethanol-treated paper because from the four sets of experiments, there was one of them in which termites prefer the control paper to ethanol-treated paper. The same trend can be observed with the treatments of pyrolysis liquid at the temperature of 500 • C when using a 5% concentration, where some termites were made contact with the treated paper at the beginning of the test and then left the paper at the end.

Previous study conducted by [START_REF] Oramahi | Antifungal and antitermitic activities of wood vinegar from vitex pubescens vahl[END_REF] has shown that wood vinegar made from pyrolysis of Vitex pubescens had repellent effect against C. formosanus and R. speratus workers. The termites exhibited significant avoidance when exposed to paper treated with 10%, 50%, and 100% concentration of wood vinegar.

Program viability of paper area measurements

The use of automatic segmentation, the k-means clustering algorithm, is feasible and simple to treat a thin substrate's image, filter paper on termites' test. The machine learning capability to differentiate the paper from the background allows us to measure the area in a high degree of precision accurately. However, a curious phenomenon could sometimes be observed during the measurement process, which was the presence of white speckles on the classified images. This could happen if the background's surface were not clean enough during the acquisition of the images. Thus, it underlined the necessity of making sure the cleanliness of the surface and camera lenses. Fig. 9.5 shows the evolution of memory utilization over time obtained by recording the program's memory utilization. Several things could be noted from these data. The first is the fact that the program used a significant amount of memory, even from the very beginning, rising from 0 to almost 500 megabytes (MB) very quickly. Even for a process that only analyzed three images (N img =3 , Fig. 9.5a), the maximum memory used exceeded 1000 MB. This should not be a surprise, seeing that Machine Learning is a branch of data science that actually still necessitates high-performance computers. It was also why many machine learning and deep learning packages available After being impregnated into 30 samples of beech wood, the average of pyrolysis liquid retention was recorded at 734.23 ± 20.59 kg/m 3 . Excluding the water contained in the pyrolysis liquid, the retention is 423.65 ± 11.88 kg/m 3 . During the oven-drying process, water and the volatile compounds from the pyrolysis liquid were released. Further, at the drying temperatures used in this study, most volatile components of pyrolysis liquid-such as methanol, acetaldehyde, formaldehyde, 2-propanol, and formic acid-are able to evaporate [START_REF] Chhiti | Thermal decomposition of bio-oil: Focus on the products yields under different pyrolysis conditions[END_REF][START_REF] Brown | Boiling point data in nist chemistry webbook[END_REF]. Fig. 9.8 presents the microscopic observation of the untreated beech wood and treated beech wood after dried at 103 • C. According to the visual observations, higher drying temperature (above 60 • C) seems to promote the agglomeration of pyrolysis liquid inside the microstructure of wood. Such agglomeration is even more noticeable in the tangential section, which fills the wood rays. As a comparison, we did not find the same agglomeration when dried the samples at ambient temperatures. [START_REF] Kim | Evaluation of the antifungal effects of bio-oil prepared with lignocellulosic biomass using fast pyrolysis technology[END_REF] stated that the chemical components of pyrolysis liquid were able to penetrate into the wood cell lumen and agglomerate forming large clusters when the volatiles were evaporated during the oven drying process. In another study, [START_REF] Lourençon | Bio-oil from a fast pyrolysis pilot plant as antifungal and hydrophobic agent for wood preservation[END_REF] also reported that the liquid product of pyrolysis acts by coating the surface of vascular microstructures of the wood.

FTIR analysis

The FTIR spectra of the untreated and treated beech wood samples were presented in the fingerprint region (1800 to 800 cm -1 ) (Fig. 9.9). The peaks observed for the untreated beech wood at this range, included peaks at 1732 cm -1 (C=O stretching) which presenting the acetyl groups in hemicelluloses, 1593 cm -1 (C=C stretching) presenting the aromatic skeletal in lignin, 1232 cm -1 (C-O stretch in lignin and xylan), and 1032 cm -1 (C-O stretching). Meanwhile, peaks at 1459 cm -1 , 1372 cm -1 , and 1158 cm -1 correspond to C-H deformation in carbohydrates and lignin, C-H deformation in cellulose and hemicellulose, and C-O-C vibration in cellulose and hemicellulose, respectively [START_REF] Grosse | Ftir-atr monitoring of chemical changes of thermo-chemically modified beech wood degraded by brown-rot fungus[END_REF]. Indeed, the FTIR spectra of treated beech wood reflect the compositions of the pyrolysis liquid and beech wood spectra [START_REF] Lourençon | Bio-oil from a fast pyrolysis pilot plant as antifungal and hydrophobic agent for wood preservation[END_REF]. The absorbance peaks at 1732 cm -1 , 1650 cm -1 , and 1593 cm -1 seem to decrease with the increase of drying, which may be related to the pyrolysis liquid content inside the wood. The C=O stretching vibrations with absorbance between 1650 and 1780 cm -1 indicate the presence of ketones, aldehydes, and carboxylic acids from the pyrolysis liquid [START_REF] Demiral | Production of biofuel from soft shell of pistachio (pistacia vera l.)[END_REF][START_REF] Islam | Properties of sugarcane waste-derived bio-oils obtained by fixed-bed fire-tube heating pyrolysis[END_REF]. However, no peak was presented as a result of the interaction between pyrolysis liquid and wood, which means that no chemical reactions occurred between them as previously confirmed by [START_REF] Lourençon | Bio-oil from a fast pyrolysis pilot plant as antifungal and hydrophobic agent for wood preservation[END_REF]. Figure 9.9: FTIR analysis of untreated and treated beech wood 9.2.2 Effect of different drying temperatures on leaching 9.2.2.1 Leachability of treated samples Fig. 9.10 shows the weight percent gain before (WPG) and after subjected to water-leaching (WPGL), as well as the leaching rate (LR) of the treated samples, with their statistical grouping presents in Tab 9.2. The difference in drying temperature gave a significant difference to the WPG, except for the samples dried at 40 • C and 60 • C. Results show that the amount of evaporated volatile compounds positively correlated with the drying temperatures. Pyrolysis liquid appears to be highly water-leachable from wood. The decrease of pyrolysis liquid content inside wood after the leaching process was even more apparent, characterized by the differences of their WPG and WPGL. However, it should be noted that at low drying temperature (below 103 • C), the weight of specimens still contain moisture. Our preliminary results indicate that at the drying temperature of 103 • C, the leaching rate was significantly lower compared to other samples. It is presumed that the presence of agglomerates caused the lower leaching rate, as they can act by blocking the water flow inside the wood, as reported by [START_REF] Lourençon | Bio-oil from a fast pyrolysis pilot plant as antifungal and hydrophobic agent for wood preservation[END_REF].

• C4 0 • C6 0 • C8 0 • C1 0 3 • C WPG abbc d WPGL abbb b LR bc ab a b c 9.2.

Analysis of the leachate compounds

The compounds leached from different treated samples is illustrated in Fig. 9.11 and Tab. 9.3. According to the GC-MS analysis, some portion of phenols, guaiacols, and ketones were leached from all the treated wood. The lower the drying temperatures, the higher portion of compounds detected by GC-MS. In this case, considering that during the drying process several compounds have been released, it is understandable that the samples dried at the temperature of 20 • C had the highest quantified compounds that were leached (77.2mg/L). Acetaldehyde was the major compound leached from the treated sample dried at 20 • C. Tab. 9.3 demonstrates the analysis results of some species quantifiable in the leachate products. However, it should be noted that the quantification is also limited due to the higher portion of water, thus reducing the concentration of the species in the leachate products. The results presented in this analysis showed that 3-methyl-1,2cyclopentanedione, 2,6-dimethoxyphenol, and phenol were the three significant compounds that leached from all the treated-wood. Previous studies highlighted the leachability as the main drawback of pyrolysis liquid when used as wood preservatives [START_REF] Mohan | Fungicidal values of bio-oils and their lignin-rich fractions obtained from wood/bark fast pyrolysis[END_REF]Temiz et al., 2013a). [START_REF] Temiz | Efficiency of bio-oil against wood destroying organisms[END_REF] reported that a significant quantity of phenolic compounds was leached during the leaching process, which was confirmed by a UV-Vis analysis. However, detailed chemical identification was not performed. A study conducted by the same author three years afterward utilized the combination of epoxidized linseed oil (ELO) to reduce the leachability of pyrolysis liquid through secondary impregnation. Their results indicated that the number of compounds determined in the leachate products was decreased from 74 to 21 when the samples were treated with 10% pyrolysis liquid and with the combination of ELO. The catechol and syringol were the most abundant compound found in the leachate products for both treatments, respectively (Temiz et al., 2013a).

20 • C4 0 • C6 0 • C8 0 • C1 0 3 • C Aldehyde Acetaldehyde 55.20 - - - - Ketones 3-methyl-

Effect of leachate products in fungal inhibition test

Tab 9.4. presents the results of the radial measurements from the four-set data test. The higher the drying temperature, the higher radial growth of mycelium, which means that it had less effect on fungi. This study also showed that T. versicolor has grown faster than C. puteana. However, when comparing the treated and untreated samples, the leachate products were more effective against C. puteana for all treatments. Indeed, from subsection 9.1.1, results suggested that pyrolysis liquid was more effective against C. puteana compared to T. versicolor. For C. puteana, no growth was observed for the treatment using leachate products from the samples dried at 20 • C, showing strong fungal activity. Further, for the leachate samples dried at 40 • C and 60 • C, half of the test samples showed no growth. As also shown in Fig. 9.12, all treatments for T. versicolor showed the mycelium growth, but slower for the treatments using lower drying temperatures. At 103 • C, the effect of the leachate products was Results and Discussion 9.2. Wood treatment using pyrolysis liquid not giving a significant difference to the growth of control. Results suggested that the leachate products were more tolerant to T. versicolor compared to C. puteana. Also, it is worth nothing that phenol-2-methoxy-4-methyl,a specific compound with anti-fungal activity, were not presented (or perhaps low in quantity) in the leachate products 80 • C and 103 • C as presented in Tab. 9.3.

20 • C4 0 • C6 0 • C8 0 • C1 0 3 • C

Resistance towards termites

The results of the termite resistance test are shown in Tab. 9.5 and the images of the samples after the test are presented in Fig. 9.13. Strong wood degradation (visual rating 4) and high termite worker survival (84 %) were observed for the control samples, thus validating the test. As expected, all the treated samples have high resistance against termites (visual rating 0 to 1), with a considerably lower weight loss compared to the control treatment. No surviving termites were found for the samples dried at 60 • C, 80 • C,a n d 103 • C, while only a very low termite survival rate was found for the specimens dried at 20 • C and 40 • C. Although the pyrolysis liquid was found to be leachable, it seems that the remaining product left in the samples is still sufficient to protect the wood.

During the experiments, we also noted that the termites were directly affected very rapidly when exposed to the treated samples. Termites tend to Table 9.5: Performance of wood treated with pyrolysis liquid after drying at different temperatures against termites (leached specimens) abstain from getting closer to the samples, and most of them hid under the sand. After two days of the test, most of the termites remained less active and gathered with one another, while significant termites were found dead in the first week of the test. Very small wood degradation were observed for all treatments (visual rating 0-1).

Weight loss after evaporation test

After being treated with 100 % pyrolysis liquid, the weight loss of beech wood samples caused by the evaporation test is lower compared to leaching, and its effect is considered negligible (Tab. 9.6). Following this found, pyrolysis liquid seems to be significantly able to be removed from the wood samples, only if the samples were exposed in high moisture or humidity condition.

Wood screening test

As previously described in the methodology section, the screening test was conducted using various concentrations of pyrolysis liquid diluted in ethanol. Specimens treated with the pyrolysis liquid before and after leaching were exposed to T. versicolor, C. puteana, and R. placenta. The correction factor for the fungal test was also presented. The whole examination aimed to determine the efficacy threshold of pyrolysis liquid using various concentrations. The samples' detailed characteristics after impregnation, leaching, and the biological performances for all of them are provided in Appendix B.

Percentage of weight gain and leaching rate

The weight percent gain before (WPG) and after leaching (WPGL) is presented in Fig. 9.14. At lower concentrations (5%, 10 %, 15 %, and 20 %), the WPG for both samples are lower than 10 %. The average WPG for beech wood samples was recorded at 2.37 % for the lowest loading treatment and 33.75 % for the highest loading treatment. For pine, the values were 2.23 % and 29.22 %, respectively. Compared to beech, pine wood samples have a lot of variation in their data distribution, possibly attributed to their anatomical characteristics (e.g., presence of the resin canal). Meanwhile, the average WPG for beech is higher possibly due to its high permeability to the impregnation. Compared to [START_REF] Lourençon | Bio-oil from a fast pyrolysis pilot plant as antifungal and hydrophobic agent for wood preservation[END_REF], our WPG is lower. In their study, WPG of using 50 % concentration was about 57 %. The WPGL of samples was considerably reduced proportionally to the initial loading of pyrolysis liquid. For the highest concentration, WPGL was reduced to 23.62% and 20.05% for the beech and pine samples, respectively. As illustrated in Fig. 9.15, the leaching rate was found high. The leaching rate showed the percentage of pyrolysis liquid that leached in the water. From the boxplot presented, therefore, it could be seen that the higher the concentration, the lower the leaching rate, as it is related to the amount of pyrolysis liquid in the wood. Almost half and more than half of products were theoretically removed during leaching for the concentration below 100 %. The lowest leaching rate was observed at 30.11% for beech samples and 31.86% for pine samples. Those values are already corrected by subtracting the values from the untreated samples. When leaching the untreated samples, some extractives could be removed. The weight loss caused by leaching for the untreated beech and pine is (1.12 ± 0.41)% and (1.57 ± 0.51)%, respectively. 9.16 shows the weight loss after the correction factor test with their moisture content recorded at the end of the test. For the highest loading treatment, the weight loss recorded for the unleached samples in this test is similar or even higher than the weight loss caused by the leaching process (see Annex. B). For beech samples, the weight loss for the correction factor is (10.31 ± 0.56) % and for the leaching is (6.93 ± 0.48)%. Meanwhile, for pine samples, the weight loss for the correction factor and due to leaching is (8.40 ± 1.59)% and (6.18 ± 0.78)%, respectively. Such findings support the fact that the pyrolysis liquid is highly leachable when exposed to high moisture and humidity. Moreover, the relative humidity in the test media was known to be at approximately 90 %. It is also interesting to note that at the end of the test, the media which the samples had the highest loading of pyrolysis liquid were observed to have the darkest color, meaning that a high portion of products was leached out into the malt-agar medium (Fig. 9.17).

Following the results, the correction factor test is thus crucial to prevent the false-positive result on the weight loss caused by the fungal attack. Using the slow pyrolysis liquid from macadamia nutshell, [START_REF] Kartal | Efficacy of tar oil recovered during slow pyrolysis of macadamia nut shells[END_REF] previously reported that the weight losses due to the fungal attack in leached specimens were less than those observed in unleached specimens; still, they did not conduct the correction factor for the fungal test. In another study, [START_REF] Tomak | The combined effects of boron and oil heat treatment on the properties of beech and scots pine wood. part 2: Water absorption, compression strength, color changes, and decay resistance[END_REF] reported that when using treated wood with a high Figure 9.16: Weight loss and moisture content of treated beech and pine wood after the correction factor test Figure 9.17: Darkest color on the malt agar medium from samples treated with the highest loading of pyrolysis liquid at the end of the test: (a) pyrolysis liquid at 10% and (b) pyrolysis liquid at 100% loading of vegetable oils, they observed high weight losses after exposed to the decay test. The oils were found to be leached out during exposure to high moisture conditions and not caused by the fungal attack. Indeed in the case of plant oils, which are often correlated as a hydrophobic substance, the drying is due to the polymerization by oxidation. However, when applied in large quantities, it will hinder the diffusion of air (oxygen) through the wood, so it requires a longer time for polymerization to occur [START_REF] Koski | Applicability of crude tall oil for wood protection[END_REF].

In some cases, there was a tendency that the moisture content or the water uptake during the test for the leached samples are lower than the unleached ones suggesting that the leaching process removed the hydrophilic substances but possibly left the hydrophobic molecules (see again Fig. 9.16). According to the microscopic observation illustrated in Fig. 9.18, some agglomeration can still be observed in the treated samples after leaching, especially those that treated using the highest loading. For the specimens diluted in ethanol, some agglomeration can still be observed, notably at the radial section. Some researchers like [START_REF] Lourençon | Bio-oil from a fast pyrolysis pilot plant as antifungal and hydrophobic agent for wood preservation[END_REF] and [START_REF] Temiz | Effect of bio-oil and epoxidized linseed oil on physical, mechanical, and biological properties of treated wood[END_REF] reported the hydrophobic properties of the liquid product from the pyrolysis process by the fact that the treated samples caused lower water absorption than those of the untreated ones. We believed such a claim is true when tested the water absorption using samples from the leaching test (see Appendix.

C, Fig. 1), as described by [START_REF] Lourençon | Bio-oil from a fast pyrolysis pilot plant as antifungal and hydrophobic agent for wood preservation[END_REF]. However, the results are more noticeable when high loadings were applied (we did not present the data using lower concentrations due to its low readability). Further, [START_REF] Panov | Using planto i l sa sh ydrophobic substances for wood protection[END_REF] also stated that when exposed under high relative humidity, the oil-treated wood swells to the same extent as the untreated wood but at a longer time to reach equilibrium. This could possibly means that the effect of pyrolysis liquid on reducing the water absorption is solely based on the agglomeration of products that hinder the water from easily penetrating the wood, as [START_REF] Koski | Applicability of crude tall oil for wood protection[END_REF] stated in the case of water repellent.

In the end, it is also important to note that the pyrolysis liquid product may differ from one another presented in the literature. Some products are described to have higher viscosity and not soluble in water, such as presented by [START_REF] Temiz | Effect of bio-oil and epoxidized linseed oil on physical, mechanical, and biological properties of treated wood[END_REF].

Decay resistance test

The results for the decay weight loss, its moisture content, and the samples after exposure (at 50% concentration) are shown in Fig. 9.19-9.24. For the control samples (virulence), the average of weight loss is always above 20%, thus validate the tests. There were significant differences in the samples that were leached or not, as expected. However, some treatments using lower loading were not significantly effective to protect the wood from the fungal attack.

Although the weight losses of the control samples were considerably higher than those of the treated ones, pyrolysis liquid at lower concentration (5% to 20 %) has low effectiveness towards T. versicolor. Some samples were even attacked similarly to the control samples. High variations on the resulting data could show that the treatments do not give enough protection to the wood. However, when treated wood with high loadings (50 % and 100 %), both concentrations give excellent protection towards decay, even for the leached samples.

For C. puteana, pyrolysis liquid seems to be more effective and consistent with their weight loss proportion when starting to use it at 10 % of concentration (retention = 50.44 kg/m 3 ). Moreover, it has been shown that C. puteana seems to be less tolerance to pyrolysis liquid, compared to T. versicolor. Meanwhile, for R. placenta the effect is noticeable when using pyrolysis liquid starts at 15 % (retention = 82.62 kg/m 3 ). Using the concentration of 50 % for both fungi was less effective when samples were leached. It is possible that some of the active ingredients, such as phenolic compounds, which are always mentioned to be responsible for the anti-fungal activity, have been removed during leaching, thus decreasing the effectiveness of pyrolysis liquid. Despite the efficacy of pyrolysis liquid, it is also important to remember the high leachability of treated wood during the test for those treated at the highest loading. It is possible that the pyrolysis liquid was leached out, then causing the fungi around the samples to die, thus slow down the fungal attack.

Indeed, the results are promising when using the highest loading, as reported in precedent studies. [START_REF] Lourençon | Bio-oil from a fast pyrolysis pilot plant as antifungal and hydrophobic agent for wood preservation[END_REF], for instance, treated the pine wood samples to reach the WPG of 57-80 % to cause complete mortality of the fungal colony of T. versicolor, while [START_REF] Kartal | Efficacy of tar oil recovered during slow pyrolysis of macadamia nut shells[END_REF] treated the pine samples with 100 % of pyrolysis liquid (retention = 460 kg/m 3 ). It is thus reasonable to use the high loading (concentration of 50% to 100%) of pyrolysis liquid to wood to maintain its efficacy. However, due to its high leachability presented in this study, pyrolysis liquid seems not effective to be used as a stand-alone method for wood protection against fungi. It is probably a potential treatment to combine with other products such as water repellent.

Termites resistance test

Tab. 9.7 shows the test results for the wood treated with pyrolysis liquid at 25 % and 50 % of concentration. Fig. 9.25 presents the samples at the end of the test. Specimens treated with ethanol are similar to the untreated ones, showing that ethanol did not significantly affect the termites' preferences. However, the weight loss and the survival rate for the control groups were lower than those presented in Tab. 9.5 due to different test time and termites. Some termites from different colonies could be bigger in their size or already full at the beginning of the test, thus affecting their eating preferences. For that reason, the virulence samples are important to carry on in every test. Following the results, although the visual rating for the specimens treated with 50 % of pyrolysis liquid provides the lowest attack (visual rating 0 to 1), there are no significant differences observed in the weight loss for both concentrations. However, the leaching treatments give the significantly lowest weight loss compared to the specimens that were not leached. For this phenomenon, [START_REF] Kartal | Efficacy of tar oil recovered during slow pyrolysis of macadamia nut shells[END_REF] previously suggested that leaching treatment could remove some beneficial compounds for the organism (e.g., source of food) or perhaps the leaching process making the distribution of bio-oil inside the wood becomes uniform. Another possibility could be caused by the product that leached out during the test, yet, the weight loss data for the termites' test was not corrected as the fungal test. Indeed in the standard, termites results were assessed only based on the visual rate. For that, the test using samples after fungal correction factor (see Fig. 9.16) were reused and exposed to termites to compare the results.

Overall, pyrolysis liquid is found effective against R. flavipes at both concentrations. Compared with the result presented in Tab. 9.5 (samples treated with 100% pyrolysis liquid after leaching), the weight loss and survival rate were similar with those treated at 50% of concentration. In another study, Temiz et al. (2013a) reported that at a concentration of 20 % (retention = 108 kg/m 3 ), bio-oil made of giant cane (Arundo donax L.) is highly effective when tested against the same termites (no weight loss and zero survival rate).

Termites test using samples from the correction factor

The treated beech wood and pine wood samples from the fungal correction factor experiments were reused for the termites' test. It is clear that some content of pyrolysis liquid had been removed due to the weight loss observed during the correction test (see again in Fig. 9.16).

For the beech samples (Tab. 9.8), the treatments with low concentrations (5% to 20%) did not show any protection against termites. However, the samples treated at 100% showed good protection with a weight loss of 2% (visual rating 1) and zero termites' survival. For the pine samples (Fig. 9.26 and Tab. 9.9), the treatments at concentration of 5% to 50% failed to give the protection against temites, except for the specimens treated at the highest concentration (100%). The weight loss recorded for such treatment was observed at 3.18-4.03%, with the visual rating from 1 to 4. The protection for the pine is lower than the beech samples probably due to different initial retention of pyrolysis liquid for both samples. Following the results on the biological tests, it is imperative to improve the stability of pyrolysis liquid to prevent leaching by means of fixation.

Conclusion

Bagasse pyrolysis liquid contains various chemicals, such as acetic acid, formic acid, propionic acid, phenols, and guaiacol derivatives, exhibiting anti-fungal and anti-termite properties. At low concentration (0.25 % in a culture media), pyrolysis liquid was able to inhibit the growth of C. puteana and T. versicolor. It also has a repellent effect on the termites, discourages the consumption activity when the paper is treated at a higher concentration of pyrolysis liquid. Filter paper treated with 10 % of pyrolysis liquid caused 100 % of termite mortality, while only 5.65 %-7.03 % of the treated filter papers consumed by termites at such concentration. Due to itse fficacity against fungi and termites, pyrolysis liquid is potentially interesting for the formulation of wood protection systems. The measurement of remained paper area in termite's bioassay using the k-means clustering method is rapid, precise, and simple to conduct. Although it clearly necessitated the utilization of a high level of random access memory, we have estimated the relationships between the number of processed images and the needed memory, thus allowing us to make a compatible strategy in choosing the number of images that could be analyzed at once based on our machine's capacity.

When treated with pyrolysis liquid only, the retention was 734.23 ± 20.59 kg/m 3 . By excluding the water from the pyrolysis liquid, the retention was 423.65 ± 11.88 kg/m 3 . In this case, it is possible to use vacuum/pressure systems without any problem. Treated wood which oven-dried at 103 • C shows lower leaching and promote agglomeration of pyrolysis liquid product inside wood cells. However, there was no indication of any chemical reaction between wood and pyrolysis liquid as shown on the FTIR results. Pyrolysis liquid is highly leachable in water, in which phenolic and guaiacol compounds were detected by GC-MS in the leachate products. The leachate products showed the lowest activity against fungi at highest drying temperature.

Pyrolysis liquid was not sufficiently compelling to protect wood against fungi when applying at low concentration (5-20%). The performance under leaching test even decreases the efficacy of pyrolysis liquid. Moreover, the fungal correction factor test suggested that pyrolysis liquid remains leachable from the wood when exposed to high humidity. A good improvemento f treated wood was observed when treated the samples at high loadings (50 and 100%). In the case of the termites' test, results suggest that pyrolysis liquid is effective when applied at concentration 25%; however, considering the instability of pyrolysis liquid, the treated wood's performance is believed to be decreased over time when exposed to high humidity.

Part IV Conclusion and Perspective

Conclusion and Perspective

General Conclusion

The valorization of biomass waste to generate bio-active chemicals is interesting given that biomass is the cheapest and most abundant resource found in large volumes, especially those that come from agricultural residue. Slow pyrolysis as a biomass thermochemical conversion method is promising for coproducing char and pyrolysis liquid in the perspective of energy densification and valorization of by-product. The recovery of condensable organic vapor for further utilization reduces the impact of air pollution, considering the conventional practice of slow pyrolysis is only intended for char generation.

In this study, sugarcane bagasse was pyrolyzed using different parameters, such as temperature (400 • C and 500 • C), heating rate (1 • C/min and 10 • C/min), and holding time (30 min and 60 min). The char generated from the process improves the properties of biomass to be used for energy. Simultaneously, the liquid product's recovery for another utilization offers an alternative route in wood protection application.

Pyrolysis temperature and heating rate had a significant influence on the char properties and the yields of products. The yield of char decrease with the increase of pyrolysis temperature but results in the favorable calorific value improvement; while at the same time generating a high mass of liquid yield. At the temperature and heating rate of 500 • C and 10 • C/min, the yield of char and pyrolysis liquid was 28.97% and 55.46%, respectively. Apart from its utilization for fuel due to the high carbon content (70.50 %) and HHV (27.85 MJ/kg), bagasse char is also potential to be used as soil amendments, as it has a high ash recovery (up to 98 %).

Pyrolysis liquid produced at different temperatures differs slightly on their proportion of chemical compositions; however, water, acetic acid, glycolaldehyde, 1-hydroxy-2-propanone, methanol, formic acid, levoglucosan, furfural, followed by some phenol compounds and guaiacol derivatives, were found as the principal compounds. Pyrolysis liquid produced at 400 • C results in slightly higher total organic contents quantified by GC-MS. From the quantification of 56 chemical compounds, the total organic contents quantified were 29.63 % and 25.63 % for pyrolysis liquid produced at 400 • C and 500 • C, respectively.

Pyrolysis liquid, which used to be a by-product of the slow pyrolysis, is a potent candidate for wood protection agents against fungi and termites. Results indicate that at low concentration (0.25 % in a culture media), pyrolysis liquid was able to inhibit the growth of C. puteana and T. versicolor. Also, it has a repellent effect on termites and is very toxic when the paper is treated at a high pyrolysis liquid concentration (10%). Various chemicals, including acetic acid, formic acid, propionic acid, phenols, and guaiacol derivatives, have been reported to exhibit anti-fungal and anti-termite activity. The synergistic effect between those compounds is likely to be responsible for its efficacy. Further, in contrast to creosote, a by-product from coal distillation, pyrolysis liquid contains no polycyclic aromatic hydrocarbon compounds (PAHs), or they were insignificant (less than 1 ppm).

Pyrolysis liquid contains considerably high water content; however, it decreases viscosity and a pre-heating process before the application can be avoided. Once incorporated in wood through vacuum impregnation, the retention of pyrolysis liquid when used alone was 734.23 ± 20.59 kg/m 3 . By excluding the water from the pyrolysis liquid, the retentioni s423.65 ± 11.88 kg/m 3 . Different drying temperatures of wood samples after being treated with pyrolysis liquid (e.g., ambient, 40, 60, 80, and 103 • C) gave significant differences in the product's loading in wood, while the high temperature (at 103 • C) seems to promote agglomeration of pyrolysis liquid product inside wood cells; however, there was no indication of any chemical reaction between wood and pyrolysis liquid as shown on the FTIR results.

Pyrolysis liquid is highly leachable in water. Compounds such as 3methyl-1,2-cyclopentanedione, phenol, 3,4-dimethylphenol , phenol-2-methoxy, phenol-2-methoxy-4-methyl, and 2,6-dimethoxyphenol were detected in the GC-MS quantification using the leachate products collected from the different drying temperatures. The leachate products also showed some activity against C. puteana and T. versicolor when incorporated in a culture media in the fungal growth inhibition test. Samples dried at ambient temperature indicates the strongest activity, notably against C. puteana.

Pyrolysis liquid was not sufficiently compelling to protect wood against fungi when applying at low concentration (5-20%). The performance under leaching test even decreases the efficacy of pyrolysis liquid. Moreover, the fungal correction factor test suggested that pyrolysis liquid remains leachable from the wood when exposed to high humidity. A good improvement of treated wood was observed when treated the samples between 50 and 100%. In the case of the termites' test, results suggest that pyrolysis liquid is effective when applied at concentration 25%; however, considering the instability of pyrolysis liquid, the treated wood's performance is believed to be decreased over time when exposed to high humidity.

In addition to those scientific results, the experiments on the termites' test using filter paper allowed us to develop a rapid, simple, and precise calculation on the paper area measurement using the k-means clustering method. Although it necessitated the utilization of a high level of random access memory, we have estimated the relationships between the number of processed images and the needed memory, thus allowing us to make a compatible strategy in choosing the number of images that could be analyzed at once based on our machine's capacity.

Perspective

Due to its anti-fungal and anti-termite properties, pyrolysis liquid is potentially interesting for the formulation of wood protection systems. However, some issues related to its acidity nature and leachability need to be highlighted prior to use it for wood protectants. Despite its goodefficacy against fungi and termites, the use of pyrolysis liquid as a stand-alone method does not seem very promising, considering its high instability once it is integrated into the wood. Wood treated with pyrolysis liquid remains highly leachable when exposed to water or high humidity, indicating that future studies should be conducted to find out how to decrease its leachability. Further study is worth carrying out, particularly in investigating the formulation strategies (fixation using the minimum product through formulation for extended efficacy through life and minimizing the impacts on human health and the environment), such as through co-impregnation with water repellents such as linseed oil and resin acid.

A. Data recapitulation: Specimens treated with crude pyrolysis liquid at different drying temperatures

I. Introduction Générale

Les résidus de biomasse végétale agricole possèdent un grand potentiel comme ressources renouvelables pour la production d'énergie et de matériaux. L'utilisation durable de la biomasse peut être implémentée en utilisant la pyrolyse avec l'objectif de la densification énergétique (conversion de la biomasse en charbon) et l'utilisation de son sous-produit comme agent protecteur du bois ou des biomatériaux. En effet, la biomasse doit être utilisée immédiatement en raison de sa propension à la biodégradation. Le potentiel de la biomasse lignocellulosique pour la production d'énergie peut être mis en oeuvre grâce à la conversion de la biomasse par pyrolyse. Ce processus transforme les matières organiques en utilisant la chaleur dans un environnement pauvre en oxygène, décompose certaines molécules constitutives de la biomasse, tels que les hémicelluloses, la cellulose et la lignine, en composés plus petits, produisant des fractions solides (charbon), liquides et gazeuses [START_REF] Mohan | Pyrolysis of wood/biomass for bio-oil: a critical review[END_REF]. En ajustant les paramètres de pyrolyse, tels que le niveau de température, la vitesse de chauffe et le temps de séjour, la quantité des produits les plus désirés peut être contrôlée [START_REF] Carrier | Comparison of slow and vacuum pyrolysis of sugar cane bagasse[END_REF].

La pyrolyse lente est une conversion énergétique largement éprouvée. Dans ce processus, la biomasse est lentement chauffée pour produire du charbon de bois, et les vapeurs organiques sont souvent simplement considérées comme des déchets. [START_REF] Bridgwater | A comparison of fast and slow pyrolysis liquids from mallee[END_REF]. Cependant, des études passées et récentes ont montré un certain intérêt pour la récupération de ce type de vapeurs organiques condensables en raison de sa grande composition en composés chimiques bioactifs tels que les acides, les phénols, les furanes et les guaiacols. Cette fraction liquide a une nomenclature variée dans la littérature, comme l'huile de pyrolyse, le liquide de pyrolyse, la bio-huile, la fumée liquide, et les distillats de bois [START_REF] Bridgwater | Renewable fuels and chemicals by thermal processing of biomass[END_REF], et ses propriétés pourraient différer les unes des autres en fonction des paramètres de pyrolyse et de la matière première utilisée. En fait, dans de nombreux pays asiatiques, la pyrolyse lente est pratiquée depuis longtemps pour produire à la fois du charbon de bois et des produits liquides [START_REF] Mathew | Pyroligneous acid-the smoky acidic liquid from plant biomass[END_REF]. Les agriculteurs traditionnels de ces pays tirent profit du produit liquide en l'utilisant comme stimulant de croissance des plantes et comme biopesticide [START_REF] Tiilikkala | Future energy transitions for bagasse cogeneration: Lessons from multi-level and policy innovations in mauritius[END_REF]. D'autre part, le bois a été massivement utilisé en raison de ses excellentes propriétés physiques, mécaniques et chimiques. Néanmoins, certaines essences ont des utilisations finales limitées en raison de leur sensibilité aux dégradations biologiques (champignons et insectes, en particulier). Dans ce cas, le liquide de pyrolyse pourrait être une voie intéressante pour la protection du bois. Plusieurs chercheurs ont montré que le liquide de pyrolyse possède une activité anti-fongique et anti-termite [START_REF] Oramahi | Antifungal and antitermitic activities of wood vinegar from oil palm trunk[END_REF][START_REF] Barbero-López | Pyrolysis distillates from tree bark and fibre hemp inhibit the growth of wooddecaying fungi[END_REF]. En outre, il a été rapporté que le liquide de pyrolyse peut être considéré comme une alternative à la créosote, ce qui est plus avantageux car il ne contient pas d'hydrocarbures aromatiques polynucléaires (HAP) (Temiz et al., 2013a), limitant ainsi l'impact sur l'environnement. Dans la littérature, l'utilisation des produits liquides dep y r o l y s ep o u rl a protection du bois est relativement limitée et présente une grande variabilité en raison des différents types de matières premières et de méthodes utilisées. C'est pourquoi, nous nous sommes concentrés sur la valorisation du liquide de pyrolyse provenant de la pyrolyse lente, qui sert généralement de produit secondaire.

Dans cette étude, la bagasse de canne à sucre, un résidu de fibrequireste après le traitement de la canne à sucre, a été utilisée comme matière première pour la pyrolyse. La biomasse est originaire de l'île de la Réunion et a été choisie comme modèle de biomasse tropicale. Le choix de la bagasse est déterminé en tenant compte de trois points : sa disponibilité, sa présence en tant que déchet ou sous-produit au lieu de matières premières, et le potentiel de sa valorisation. De plus, à notre connaissance, il n'y avait pas de précédent de recherche sur le liquide de pyrolyse obtenu à partir de la bagasse de canne à sucre pour une application de traitement du bois. La conversion de la bagasse de canne à sucre en charbon de bois pour la production d'énergie pourrait également permettre de résoudre les problèmes de saisonnalité et de biodégradabilité de cette biomasse. Étant une plante saisonnière, la bagasse doit être stockée si elle doit être utilisée en dehors de sa période de récolte maximale. De plus, étant un matériau hygroscopique, la bagasse est sujette à des changements d'humidité pendant le stockage et à la biodégradation [START_REF] Breccia | Degradation of sugar cane bagasse by several white-rot fungi[END_REF][START_REF] Dong | Sugarcane bagasse degradation and characterization of three white-rot fungi[END_REF]. Pour surmonter ces problèmes, la conversion thermochimique de la bagasse peut être appliquée en la transformant en un charbon riche en carbone, qui peut ensuite être stocké sans aucune dépertition d'énergie. En outre, jusqu'à présent, peu d'études ont porté sur un processus de co-valorisation de la biomasse couplant (i) le processus de pyrolyse pour produire de l'énergie et des gaz, et (ii) la conservation et la valorisation des composés chimiques condensables issus de ce premier processus thermochimique en composés chimiques de valeur, plus particulièrement pour leurs activités anti-fongiques et anti-termites. Les principaux objectifs de ces travaux seront les suivants:

1. Déterminer la condition optimale du paramètre du processus de pyrolyse pour la co-production du charbon et du liquide de pyrolyse.

2. Évaluer la composition chimique et les activités anti-fongiques et antitermites du liquide de pyrolyse sélectionné.

3. Traiter le liquide de pyrolyse dans les échantillons de bois pour étudier son potentiel de protection du bois, déterminer la température de séchage optimale, analyser ses propriétés de lessivage et obtenir le seuil de concentration efficace contre les champignons et les termites.

Cette thèse est divisée en quatre parties. La première partie est consacrée à l'analyse bibliographique sur la valorisation de la biomasse par pyrolyse et le potentiel du liquide de pyrolyse pour la protection du bois. Les deuxième et troisième parties couvrent les résultats des travaux expérimentaux menés dans cette étude. La deuxième partie présente les travaux sur les paramètres de la pyrolyse lente et leur effet sur les propriétés de carbonisation et le rendement du charbon et du liquide de pyrolyse, ainsi que la composition chimique du liquide de pyrolyse. La troisième partie présente les résultats des essais biologiques sur les anti-fongiques et les anti-termites du liquide de pyrolyse dans les boîtes de Pétri, le développement de la mesure de la surface du papier en utilisant la méthode de k-means clustering pour l'essai sur les termites, et le traitement du bois avec le liquide de pyrolyse tout en étudiant son efficacité contre les champignons et les termites. Enfin, la dernière partie présente la conclusion générale sur le travail et les résultats, ainsi que les perspectives pour les travaux futurs.

II. Valorisation énergétique de la bagasse de canne à sucre par pyrolyse lente

Introduction

Cette partie présente les résultats des études sur la valorisation de la bagasse de canne à sucre par pyrolyse lente. La bagasse a été convertie pour produire du charbon et du liquide de pyrolyse en utilisant un réacteur de laboratoire à lit fixe. Comme mentionné précédemment, la pyrolyse lente, qui se produit à une faible vitesse de chauffe et un long temps de séjour, produit un charbon de bonne qualité [START_REF] Bridgwater | Renewable fuels and chemicals by thermal processing of biomass[END_REF]. Cette technique est intéressante pour convertir la biomasse instable, qui contient plus de volatils, comme la bagasse, pour obtenir un produit stable et riche en énergie. Le charbon peut également être utilisé pour la production d'électricité ou être valorisé comme un produit de grande valeur comme le charbon actif et les amendements du sol [START_REF] Pecha | Pyrolysis of lignocellulosic biomass: oil, char, and gas[END_REF].

Des études précédentes ont montré que la pyrolyse lente de la bagasse est optimale pour produire le rendement de charbon le plus élevé à une vitesse de chauffe entre 2 • C/min et 16 • C/min et à une température de plus de à 240 • C, des différences significatives de perte de masse se produisant à des températures entre 300 • C et 500 • C [START_REF] Katyal | Carbonisation of bagasse in a fixed bed reactor: influence of process variables on char yield and characteristics[END_REF][START_REF] Carrier | Comparison of slow and vacuum pyrolysis of sugar cane bagasse[END_REF]. À partir de ces résultats, nous avons pu établir les expérimentations de pyrolyse lente à une vitesse de chauffe plus basse (1 • C/min et 10 • C/min) et à une température intermédiaire (400 • C et 500 • C), car une bonne qualité de charbon pouvait être obtenue avec ces gammes de températures [START_REF] Demirbas | The influence of temperature on the yields of compounds existing in bio-oils obtained from biomass samples via pyrolysis[END_REF].

L'objectif de notre étude est donc d'évaluer le potentiel de la valorisation de la bagasse par pyrolyse lente. Le charbon résultant ded i fférents paramètres de pyrolyse a été évalué en fonction de son rendement, des analyses immédiates et ultimes, et de son pouvoir calorifique pour évaluer son potentiel en tant que source d'énergie. Nous avons récupéré le liquide de pyrolyse issu du processus de condensation pour qu'il serve de candidat en tant qu'agent de protection du bois. La composition chimiqued e sl i q u i d e s de pyrolyse sélectionnés à partir du processus a également été examinée.

Matériel et méthods

La bagasse de canne à sucre (Saccharum spp.) avec une taille de particule inférieure à 2m ma été utilisé pour les essais de pyrolyse. La pyrolyse a été fait à une température de 400 • C et 500 • C, à une vitesse de chauffe de 1 • C/min et 10 • C/min, et temps de séjour de 30 min et 60 min, dans un réacteur à lit fixe à l'échelle du laboratoire. Le réacteur est également équipé d'un système de condensation qui a permis de condenser et de refroidir les produits volatils générés par la pyrolyse pour produire le liquide de pyrolyse.

L'analyse immediate, ultime et calorifique, la récupération des cendres, le rendement énergétique et la densité énergétique de la bagasse et du charbon ont été caractérisés. La composition chimique du liquide de pyrolyse (produit à 400 et 500 • C, à une vitesse de chauffe 10 • C/min, et temps de séjour de 60 min) a été étudiée à l'aide de la GC-MS et de la FTIR. La teneur en eau du liquide de pyrolyse a été déterminée à l'aide d'un titrage volumétrique Karl Fisher.

Une analyse de régression multivariée a été faite pour déterminer la corrélation de chaque paramètre et ses effets sur les valeurs de rendement et les propriétés des charbons. La température, la vitesse de chauffe et le temps de séjour étaient les paramètres indépendants. Nous avons ensuite déterminé statistiquement l'impact de chacun de ces paramètres, individuellement, en utilisant la valeur p et globalement en voyant leur valeur R 2 .

Résultats et discussion

La bagasse contient 8,5% d'humidité, 82,4% de matières volatiles, 13,4% de carbone fixe, et 4,2% de cendres. La bagasse contient également un très faible ratio carbone fixe / matières volatiles en raison de la forte teneur en matières volatiles. La bagasse contient 47,3% de carbone, 5,7% d'hydrogène, 0,4% d'azote, et 46,7% d'oxygène et de soufre totaux. Le HHV était de 18,14 MJ/kg. L'analyse démontre que la biomasse étudiée est comparable aux autres bagasses de canne à sucre rapportées dans différentes études.

La température a été mise en évidence comme le paramètre le plus important, influençant le rendement en charbon et le rendement en liquide. Les deux vitesses de chauffe( 1 • C/min et 10 • C/min) ont également montré un effet significatif sur le rendement en charbon et en liquide. Par ailleurs, il n'y a pas de différence significative dans les rendements des produits pour le temps de séjour de 30 min et 60 min. Dans toutes les conditions testées, la moyenne du rendement en charbon et en liquide a varié entre 28,81%-35,12%, et 49,67%-55,46%.

La température et la vitesse de chauffe ont influencé de manière significative la teneur en matières volatiles, cendres, carbone fixe, carbone élémentaire et HHV, tandis que le temps de séjour ne contribue qu'à la teneur en matières volatiles. Après avoir été pyrolysée, la bagasse carbonisée a une teneur en matières volatiles de 24,31%-25,80% à 400 • C, et de 13,01%-16,43% à 500 • C. Le carbone fixe le plus élevé a été observé à 68,50%-73,01%. La teneur en cendres varie de 10,79%-15.50%, inférieure à la teneur en cendres de l'étude conduite par Varma and Mondal (2017) (16,25%). Les taux élevés III. Performances des liquides de pyrolyse pour la protection du bois

Introduction

Cette partie présente les potentialités d'utilisation du liquide de pyrolyse pour la protection du bois. Comme cela a été précédemment rapporté, son utilisation est déjà effective dans de nombreux domaines tels que les biocides, les insecticides, les fongicides, les stimulateurs de croissance des plantes et comme source de produits chimiques à forte valeur ajoutée [START_REF] Tiilikkala | Future energy transitions for bagasse cogeneration: Lessons from multi-level and policy innovations in mauritius[END_REF][START_REF] Mathew | Pyroligneous acid-the smoky acidic liquid from plant biomass[END_REF][START_REF] Pimenta | Chemical composition of pyroligneous acid obtained from eucalyptus gg100 clone[END_REF]. En raison de sa grande composition en produits chimiques bioactifs, tels que les acides organiques, les phénols, les cétones, les aldéhydes, les furanes et les guaiacols, le liquide de pyrolyse était supposé protéger le bois contre les champignons et les termites (Temiz et al., 2013a). [START_REF] Barbero-López | Pyrolysis distillates from tree bark and fibre hemp inhibit the growth of wooddecaying fungi[END_REF] a indiqué que les distillats de pyrolyse issues d'écorce d'épicéa et de bouleau, de fibres de chanvre obtenues à des températures de 275 • C-350 • C permettent d'inhiber la croissance des champignons de pourriture du bois. [START_REF] Oramahi | Antifungal and antitermitic activities of wood vinegar from oil palm trunk[END_REF] ont également étudié le liquide de pyrolyse du stipe du palmier à huile à un 350 • C comme anti-termite.

Dans cette étude, nous avons utilisé les liquides de pyrolysebrutsobtenus à partir des nos expériences de pyrolyse. Le liquide de pyrolyse a tout d'abord été testé pour déterminer le seuil d'efficacité contre les champignons et les termites. Le liquide de pyrolyse utilisé a été obtenu à partir des températures de 400 • C et de 500 • C, de la vitesse de chauffe de 10 • C/min, et du temps de séjour de 60 min. Pour le test d'efficacité vis-à-vis des termites, une méthode rapide de mesure de la surface de papier résiduel consommée par les termites a été dévéloppée.

Le traitement du bois a ensuite été réalisé en utilisant le liquide de pyrolyse produit à une température de 500 • C, une vitesse de chauffe de 10 • C/min, et un temps de séjour de 60 min. Comme test préliminaire, nous avons voulu évaluer l'effet de différentes températures de séchage sur les échantillons traités. L'effet du lessivage a également été étudié, ainsi que l'analyse chimique des eaux de lessivage et leur potentiel anti-fongique. Enfin, les échantillons après lessivage ont été testés pour leur efficacité contre les termites Reticulitermes flavipes.

Après avoir déterminé les températures de séchage souhaitables pour les échantillons de bois, le processus d'imprégnation a été réalisé par vide/pression en utilisant le liquide de pyrolyse à différentes concentrations. Dans cette étape, l'efficacité et le seuil de concentration du liquide de pyrolyse vis-à-vis des champignons et des termites ont été évalués. L'effet du lessivage et de essai, cinq températures de séchage différentes ont été testées (20 • C, 40 • C, 60 • C, 80 • C, et 103 • C.) La masse des échantillons après séchage a ensuite été enregistrée pour déterminer le pourcentage de gain de masse (WPG). La microstructure des échantillons de bois traité a été observée à l'aide d'un appareil photo numérique Nikon DS Fi1 connecté à un microscope optique (Olympus BX6). Les spectres FTIR du hêtre traité et non traité ont également été enregistrés.

Un autre essai d'imprégnation a été réalisé en utilisant différentes concentrations de liquide de pyrolyse (5%, 10%, 15%, 20%, 25%, et5 0 % )d i l u é dans de l'éthanol (v/v)

Lessivage

Le test de lessivage a été fait selon la norme NF X 41-568 (2014) où les échantillons traités ont été soumis à six périodes de lessivage successives (1h, 2h, 4h, et 8h, 16 h, et 48 h) dans de l'eau déionisée (1 vol de bois/5 vol d'eau déionisée). Le pourcentage en masse après lessivage (WPGL) et le pourcentage du taux de lessivage (LR) ont été déterminés.

Pour les échantillons traités qui ont séché à différentes températures, les produits de lessivage ont été collectés pour être analysés par GC-MS. Les produits de lessivage ont été utilisés pour un test d'inhibition des champignons afin de déterminer si la solution de lessivage contient des composés bio-actifs.

Test de durabilité contre les champignons et les termites

Le test fongique a été réalisé selon la méthode inspirée de la norme EN 113-1 (2020) en utilisant trois types de champignons responsables de la pourriture du bois : une pourriture blanche (Trametes versicolor ) et deux pourriture brunes (Coniophora puteana et Rhodonia placenta). Le facteur de correction (de la perte de masse due à l'action fongique) a également été détérminé pour évaluer la perte de poids des échantillons causée par l'attaque non fongique (causée par la libération de produits pendant let e s t ) . L et e s t a été effectué pendant huit semaines.

Le test de résistance aux termites a été évalué selon un test de non choix, inspiré de la norme européenne EN 117 (2013). A l'issue de l'essai, une cotation visuelle, été attribuée à chaque échantillon, la perte de masse du bois et le taux de survie ont été déterminés. Le test a été effectué pendant quatre semaines.

Résultats et discussion

Deux types de liquide de pyrolyse ont été révélés efficaces pour inhiber la croissance de C. puteana et T. versicolor. Pour inhiber complètement la croissance fongique, un liquide de pyrolyse à une concentration de 0,20% bois, ce qui montre qu'aucune réaction chimique ne s'est produite entre eux, comme le confirme [START_REF] Lourençon | Bio-oil from a fast pyrolysis pilot plant as antifungal and hydrophobic agent for wood preservation[END_REF].

Le liquide de pyrolyse semble être hautement lessivable du bois. Le taux de lessivage était plus faible pour les échantillons séchés à 103 • C. Selon l'analyse par GC-MS, une partie des phénols, des guaiacols et des cétones ont été lessivés. Plus les températures de séchage sont basses, plus la proportion de composés détectés par GC-MS est élevée. Le 3-méthyl-1,2cyclopentanedione, le 2,6-diméthoxyphénol et le phénol sont les trois principaux composés qui ont été lessivés de tout le bois traité.

Pour le test d'inhibition fongique utilisant les eaux de lessivage, nous avons observé que plus la température de séchage est élevée, plus la croissance radiale du mycélium est importante, ce qui signifie qu'il a moins d'effet sur les champignons. En revanche, aucune croissance n'a été observée pour le traitement utilisant des produits de lessivage à partir des échantillons de lessive séchés à 20 • C, ce qui montre une forte activité fongique.

Pour le test biologique contre les termites et les champignons, les résultats montrent une bonne efficacité lorsque les échantillons ont été traités avec une forte charge de liquide de pyrolyse (50% et 100%). Le principal désavantage du liquide de pyrolyse pour la protection du bois est sa lessivage élevée dans l'eau ou à l'état humide, comme le montre le résultat du facteur de correction fongique ou le test de reprise d'eau.

IV. Conclusion et Perspective

Conclusion Générale

La valorisation des déchets de biomasse agricole pour générer des produits chimiques bio-actifs est intéressante étant donné que la biomasse est la ressource la moins chère et la plus abondante que l'on trouve en grand volume. La pyrolyse lente comme méthode de conversion thermochimique de la biomasse est intéressante pour la co-production de charbon et de liquide de pyrolyse dans la perspective de la densification énergétique et de la valorisation du sous-produit. La récupération de la vapeur organique condensable pour une utilisation future réduit l'impact de la pollution de l'air, considérant que la pratique conventionnelle de la pyrolyse lente est uniquement destinée à la production de charbon.

Dans cette étude, la bagasse de canne à sucre a été pyrolysée enu t i li s a n t différents paramètres, tels que la température (400 • C et 500 • C), la vitesse de chauffe(1 • C/min et 10 • C/min), et le temps de séjour (30 min et 60 min). Le charbon généré par ce processus permet de concentrer l'énergie. Simultanément, la récupération du produit liquide pour une autre utilisation offre une voie alternative pour la protection du bois.

La température de pyrolyse et la vitesse de chauffe ont eu une influence significative sur les propriétés de charbon et le rendement des produits. Le rendement du charbon diminue avec l'augmentation de la température de pyrolyse mais résulte en une amélioration de la valeur calorifique; tout en générant une masse élevée de rendement liquide. Outre son utilisation comme combustible en raison de sa teneur élevée en carbone (70,50%) et en HHV (27,85 MJ/kg), le charbon de bagasse est également potentiellement utilisable comme amendement du sol, due à une haute récupération desc e n d r e s (jusqu'à 98%).

Le liquide de pyrolyse produit à différentes températures présente une légère différence dans les proportions de leur composition chimique; cependant, l'eau, l'acide acétique, le glycolaldéhyde, la 1-hydroxy-2-propanone, le méthanol, l'acide formique, le lévoglucosane, le furfural, suivis de quelques composés phénoliques et de dérivés du guaiacol, ont été trouvés comme composés principaux. Le liquide de pyrolyse produit à 400 • C donne un contenu organique total légèrement plus élevé lorsque quantifié par GC-MS. Sur la base de la quantification de 56 composés chimiques, les teneurs organiques totales quantifiées étaient respectivement de 29,63% et de 25,63% pour le liquide de pyrolyse produit à 400 • C et 500 • C.

Le liquide de pyrolyse est un candidat potentiel pour la protection du bois contre les champignons et les termites. Les résultats démontrent qu'à de faibles concentrations (0,25%), le liquide de pyrolyse est capable d'inhiber la croissance de C. puteana et de T. versicolor, a également un effet répulsif et toxique vis-à-vis des termites (en particulier à forte concentration (10%)). Divers composés, dont l'acide acétique, l'acide formique, l'acide propionique, les phénols, et les dérivés du guaiacol, ont été rapportés comme ayant une activité anti-fongique et anti-termites. L'effet synergique entre ces composés est probablement responsable de son efficacité. En outre, contrairement à la créosote, un sous-produit de la distillation du charbon, le liquide de pyrolyse ne contient pas de composés d'hydrocarbures aromatiques polycycliques (HAP), ou alors ils sont insignifiants (moins de 1 ppm).

Le liquide de pyrolyse a une teneur en eau considérablement élevée; cependant, cela réduit sa viscosité et le processus de préchauffage avant l'application sur le bois peut être évité. Une fois incorporé dans le bois par imprégnation sous vide, la rétention du liquide de pyrolyse était de 734, 23 ± 20, 59 kg/m 3 . En excluant l'eau, la rétention est de 423,65 ±11, 88 kg/m 3 . Les différentes températures de séchage des échantillons de bois après avoir été traités avec le liquide de pyrolyse (ambiante, 40, 60, 80 et 103 • C) ont donné des différences significatives dans la charge du produit dans le bois, tandis que la température élevée (à 103 • C) semble favoriser l'agglomération du produit liquide de pyrolyse à l'intérieur des cellules du bois. Nous n'avons toutefois pas eu d'indication de réaction chimique entre le bois et le liquide de pyrolyse comme le montrent les résultats de FTIR.

Le liquide de pyrolyse est hautement lessivable dans l'eau. Des composés tels que la 3-méthyl-1,2-cyclopentanedione, le phénol, le 3,4-diméthylphénol, le phénol-2-méthoxy, le phénol-2-méthoxy-4-méthyle et le 2,6-diméthoxyphénol ont été détectés lors de la quantification par GC-MS en utilisant les produits de lessivage collectés à différentes températures de séchage. Les produits de lessivage ont également montré une certaine activité contre C. puteana et T. versicolor dans le test d'inhibition de la croissance fongique, où les échantillons séchés à température ambiante indiquent l'activité la plus forte, notamment contre C. puteana.

Selon les résultats obtenus, le liquide de pyrolyse n'était pas suffisamment efficace pour protéger le bois contre les champignons lorsqu'il était appliqué à faible concentration (5% à 20%). De plus, le test du facteur de correction fongique suggère que le liquide de pyrolyse reste lessivable du bois lorsqu'il est exposé à une forte humidité. Une bonne amélioration de l'efficacité a été observée lorsque les échantillons ont été traités à des charges élevées (entre 50% et 100%). Dans le cas du test sur les termites, les résultats suggèrent que le liquide de pyrolyse est efficace lorsqu'il est appliqué à une concentration de 25%; cependant, compte tenu de l'instabilité du liquide dep y r o l y s e ,o n pense que la performance du bois traité diminue avec le temps lorsqu'il est exposé à une humidité élevée.

En plus de ces résultats scientifiques, les expérimentations sur les termites à l'aide de papier filtre nous ont permis de développer un calcul rapide, simple et précis sur la mesure de la surface du papier en utilisant la méthode de kmeans clustering. Bien que cela ait nécessité l'utilisation d'un niveau élevé de mémoire vive, nous avons estimé les relations entre le nombre d'images traitées et la mémoire nécessaire, ce qui nous a permis d'élaborer une stratégie compatible pour choisir le nombre d'images qui pouvaient être analysées à la fois en fonction de la capacité de notre machine.

Perspective

Grâce à ses propriétés anti-fongiques et anti-termites, le liquide de pyrolyse est potentiellement intéressant pour la formulation de systèmes de protection du bois. Néanmoins, certaines problématiques liées à son acidité et sa lessivabilité doivent être prises en compte avant de l'utiliser pour la protection du bois. Nos résultats montrent que l'utilisation du liquide de pyrolyse comme méthode seule ne semble pas très prometteuse,e nr a i s o nd e sa grande instabilité une fois qu'il est intégré dans le bois.L eb o i st r a i t é avec le liquide de pyrolyse reste très lessivable lorsqu'il est exposé à l'eau ou à une forte humidité, ce qui indique que des études futures devraient être menées pour trouver comment réduire sa lessivabilité. D'autres études sont nécessaires, notamment pour évaluer les stratégies de formulation (fixation à l'aide du produit minimum par la formulation pour une efficacité prolongée tout au long de la vie et la minimisation des impacts sur la santé humaine et l'environnement), comme par exemple par co-imprégnation avec des agents hydrophobes tels que l'huile de lin et l'acide résinique.

  charcoal making process (left) and its by-product from the condensation of smoke (right)[START_REF] Kishimoto | Wood vinegar and biochar in agriculture[END_REF] ................................ 42 4.1 Sugarcane bagasse ........................ 55 4.2 Experimental set-up of the pyrolysis reactor: (1) temperature control, (2) nitrogen gas supply, (3) flow control, (4) muffle furnace, (5) pyrolysis reactor, (6a and 6b) thermocouples, (7) bagasse/char, (8) condenser, (9) condensed liquid, (10) cooling bath, (11) electrostatic precipitator, (12) light product, and (13) gas vent ........................... 56 4.3 Pyrolysis liquid of sugarcane bagasse .............. 57 4.4 FTIR device ............................ 60 5.1 Comparison between the expected pyrolysis process (T model) and experiment (T experimental) at temperature of 500 • C and heating rate of 1 • C/min (a) and at temperature of 400 • C and heating rate of 10 • C/min (b) .................. 65 5.2 FTIR spectra of pyrolysis liquid (PL) at the temperature of 400 • C and 500 • C ......................... 74 8.1 Termites test device for the choice test using one Joseph filter paper (diameter of Petri-dish = 9cm) .............. 84 8.2 Termites test device for the repellency test using two Joseph filter papers (diameter of Petri-dish = 14 cm) .......... 85 8.3 Workflow of the image processing using Python from the original image to the exported results ................ 87 8.4 Steps of image processing, from original picture(a) to segmented (b) and thresholded image (c) .............. 89 8.5 Leaching process ......................... 93 8.6 Fungal test device with wood specimens ............ 95 8.7 Termites test device with wood specimen ............ 97 9.1 Inhibition rate of C. puteana (a) and T.versicolor (b) at different concentrations (bar followed by the same letter are not significantly different) .......................100 9.2 Growth of C. puteana (a = control; b = pyrolysis liquid at 0.10 % concentration; c = pyrolysis liquid at 0.20 % concentration) and T. versicolor (a = control; b = pyrolysis liquid at 0.10 % concentration; c = pyrolysis liquid at 0.20 % concentration) ..............................101 LIST OF FIGURES xv 9.3 Percentage of paper loss area and termite's mortality (bar followed by the same letter are not significantly different) ....102 9.4 Paper consumed by termites (a = control (water); b = control (ethanol); c = pyrolysis liquid at 5% of concentration and d = pyrolysis liquid at 10 % of concentration) ...........103 9.5 Evolution of memories used by the code (non-GUI version) over time for various total number of images ..........106 9.6 Relationships between total number of processed images, processing time, and maximum memories used ...........107 9.7 Untreated and treated beech wood samples after drying ....108 9.8 Microscopic observation using a light microscopy: (a) untreated beech wood at longitudinal section; (b) untreated beech wood at radial section; (c) untreated beech wood at tangential section; (d) treated beech wood -103 • C at longitudinal section; (e) treated beech wood -103 • C at radial section; (f) treated beech wood -103 • C at tangential section. ...........109 9.9 FTIR analysis of untreated and treated beech wood ......110 9.10 Weight percent gain before and after leaching (a) and leaching rate (b) of the treated samples when dried at different temperatures ...........................111 9.11 Compounds leached from the treated-wood specimens that dried at different temperatures ..................112 9.12 The growth of C. puteana and T.versicolor at different leachate products: (a) 20 • C; (b) 40 • C; (c) 60 • C; (d) 80 • C; (e) 103 • C; (f) control .............................114 9.13 Beech wood samples at the end of termites' test ........115 9.14 Weight percent gain before (WPG) and after leaching (WPGL) for beech wood and pine wood samples at various concentrations of pyrolysis liquid ......................117 9.15 Leaching rate for beech wood and pine wood samples at various concentrations of pyrolysis liquid ..............118 9.16 Weight loss and moisture content of treated beech and pine wood after the correction factor test ...............119 9.17 Darkest color on the malt agar medium from samples treated with the highest loading of pyrolysis liquid at the end of the test: (a) pyrolysis liquid at 10% and (b) pyrolysis liquid at 100%120 9.18 Microscopic observation of treated wood samples after leaching (a) tangential section treated with 100% concentration of pyrolysis liquid, and (b) radial section treated with 50% of radial section ...........................121 xvi LIST OF FIGURES 9.19 Weight loss of beech specimens and their moisture content after exposed to T. versicolor (WL is corrected with the correction factor) ...........................122 9.20 Beech samples at the end of decay test (exposed to T. versicolor )122 9.21 Weight loss of pine specimens and their moisture content after exposed to C. puteana (WL is corrected with the correction factor) ...............................123 9.22 Pine samples at the end of decay test (exposed to C. puteana) 123 9.23 Weight loss of pine specimens and their moisture content after exposed to R. placenta (WL is corrected with the correction factor) ...............................124 9.24 Pine samples at the end of decay test (exposed to R. placenta) 124 9.25 Beech wood samples treated with different concentration of pyrolysis liquid at the end of the termites' test .........126 9.26 Samples of pine at the end of termites' test (leached specimens)127 1W atera bsorptiond uringl eachingt estu singb eechs amples dried at different temperatures ..................163

Figure 1

 1 Figure 1.4: Basic units of lignin

Figure 1 .

 1 Figure 1.7: Bagasse storage facility to generate heat and electricity (To et al., 2018)

Figure 1 . 9 :

 19 Figure 1.9: Composition of lignocellulosic materials and their potential hydrolysis products with further degradation compounds (HMF = Hydroxymethylfurfural)[START_REF] Taherzadeh | Acid-based hydrolysis processes for ethanol from lignocellulosic materials: a review[END_REF]

Figure 1 .

 1 Figure1.11: TG (full lines) and DTG (dashed line) curves for cellulose, hemicellulose, and lignin at a heating rate of 10 • C/min[START_REF] Yang | Characteristics of hemicellulose, cellulose and lignin pyrolysis[END_REF][START_REF] Ronsse | Carbonization of biomass[END_REF]

Figure 1 .

 1 Figure1.13: Soil amended by biochar called "terra preta" on the right improves the crop yield compare to unamended soil on the left[START_REF] Pecha | Pyrolysis of lignocellulosic biomass: oil, char, and gas[END_REF]

Figure 2 . 2 :

 22 Figure 2.2: Attack of fungi on wood: a) brown-rot (Goodell, 2020); b) whiterot (Auró 2016); c) soft-rot (Mariano et al., 2020); d) blue stain[START_REF] Goodell | 15 fungi involved in the biodeterioration and bioconversion of lignocellulose substrates[END_REF]; and e) mold[START_REF] Imken | Resistance of different wood-based materials against mould fungi: a comparison of methods[END_REF]

Figure 2 . 3 :

 23 Figure 2.3: The condesable vapors of slow pyrolysis process

4. 1 . 1

 11 Biomass preparationSugarcane bagasse (Saccharum spp.) was obtained from three consecutive annual harvests from la Réunion Island (French overseas territory) (Fig.4.1).

Figure

  Figure 4.1: Sugarcane bagasse

Figure 4 . 2 :

 42 Figure 4.2: Experimental set-up of the pyrolysis reactor: (1) temperature control, (2) nitrogen gas supply, (3) flow control, (4) muffle furnace, (5) pyrolysis reactor, (6a and 6b) thermocouples, (7) bagasse/char, (8) condenser, (9) condensed liquid, (10) cooling bath, (11) electrostatic precipitator, (12) light product, and (13) gas vent

Figure 4 . 3 :

 43 Figure 4.3: Pyrolysis liquid of sugarcane bagasse

1

 1 Water content and pH of pyrolysis liquid

Figure

  Figure 4.4: FTIR device

Figure 5 . 1 :

 51 Figure 5.1: Comparison between the expected pyrolysis process (T model) and experiment (T experimental) at temperature of 500 • C and heating rate of 1 • C/min (a) and at temperature of 400 • C and heating rate of 10 • C/min (b)

Figure 5 . 2 :

 52 Figure 5.2: FTIR spectra of pyrolysis liquid (PL) at the temperature of 400 • C and 500 • C

2

 2 Termites non-choice test/toxic effectTermites non-choice test was evaluated using the pyrolysis liquid produced at the temperature of 400 • C and 500 • C, a heating rate of 10 • C/min, and a holding time of 60 min. The non-choice test was conducted against Reticulitermes flavipes (ex. santonensis) termites using a Joseph filter paper (grammage 25 g/m 3 ) made of pure cellulose (diameter of 42.5mm). Pyrolysis liquid was diluted in ethanol (Honeywell) (v/v) at a 5% and 10 % concentration and treated to the filter paper by immersing them for 60 s.T w o control were also prepared by soaking the filter paper in deionized water and ethanol, separately. Six replicates were performed for each treatment. Prior to the test, all of the treated filter papers were air-dried for at least 10 min or 20 min for paper treated with water.

Figure 8 . 1 :

 81 Figure 8.1: Termites test device for the choice test using one Joseph filter paper (diameter of Petri-dish = 9cm)

8. 1 . 3

 13 Termites choice test/repellent effectTermites choice test was evaluated using the pyrolysis liquid produced at the temperature of 400 • C and 500 • C, a heating rate of 10 • C/min, and a holding time of 60 min. Two sets of Joseph filter paper (grammage 25 g/m 3 ) made of pure cellulose (diameter of 42.5mm) were used to evaluate the repellent effect of pyrolysis liquid toward R. flavipes. Each paper was treated with only ethanol or pyrolysis liquid diluted in ethanol (Honeywell) (v/v) at a concentration of 5%, 10 %, and 20 %. Meanwhile, another was set-up as control (treated with deionized water). The control and treated paper were placed inside a 140-mm diameter Petri-dish, which were separated approximately 15 mm apart (Fig.8.2). Then, a total amount of 20 termites workers were introduced in each Petri-dish.

Figure 8 . 2 :

 82 Figure 8.2: Termites test device for the repellency test using two Joseph filter papers (diameter of Petri-dish = 14 cm)

8. 1 . 4

 14 Method development for paper area measurement 8.1.4.1 Image analysis using image segmentation and k-means clustering

Figure 8

 8 Figure 8.5: Leaching process

  two brown-rots (Coniophora puteana, strain BAM Ebw. 15 and Rhodonia placenta, strain FPRL 280). Samples of beech wood were exposed to T. versicolor, while the samples of pine sapwood were exposed to C. puteana and R. placenta, separately. The malt-agar medium was prepared by mixing 40 g of malt (Quaron) and 20 g of agar (Biomerieux) in 1L of deionized water (water quality 3) and sterilized using an autoclave, at 121 • C for 20 min. The sterile culture medium (65 ml) then poured into a culture flask. Two small pieces of mycelium from a growing fungal culture were inoculated inside the culture flask and incubated for two weeks at (22 ± 2) • C and (70 ± 5) % RH to allow full colonization of the medium by the mycelium.

Figure 8 . 6 :

 86 Figure 8.6: Fungal test device with wood specimens

Figure 8

 8 Figure 8.7: Termites test device with wood specimen

Figure 9 . 2 :

 92 Figure 9.2: Growth of C. puteana (a = control; b = pyrolysis liquid at 0.10 % concentration; c = pyrolysis liquid at 0.20 % concentration) and T. versicolor (a = control; b = pyrolysis liquid at 0.10 % concentration; c = pyrolysis liquid at 0.20 % concentration)

Figure 9 . 4 :

 94 Figure 9.4: Paper consumed by termites (a = control (water); b = control (ethanol); c = pyrolysis liquid at 5% of concentration and d = pyrolysis liquid at 10 % of concentration)

  Fig 9.7 shows the untreated and treated beech wood (with 100% pyrolysis liquid) after being dried at different temperatures. The higher the drying temperature, the darker the wood. The air-dried samples had more pungent odor than other specimens.

Figure 9 . 7 :

 97 Figure 9.7: Untreated and treated beech wood samples after drying

Figure 9

 9 Figure 9.8: Microscopic observation using a light microscopy: (a) untreated beech wood at longitudinal section; (b) untreated beech wood at radial section; (c) untreated beech wood at tangential section; (d) treated beech wood -103 • C at longitudinal section; (e) treated beech wood -103 • C at radial section; (f) treated beech wood -103 • C at tangential section.

Figure 9 .

 9 Figure 9.10: Weight percent gain before and after leaching (a) and leaching rate (b) of the treated samples when dried at different temperatures

Figure 9 .

 9 Figure 9.11: Compounds leached from the treated-wood specimens that dried at different temperatures

Figure 9 .

 9 Figure 9.12: The growth of C. puteana and T.versicolor at different leachate products: (a) 20 • C; (b) 40 • C; (c) 60 • C; (d) 80 • C; (e) 103 • C; (f) control

  Figure 9.13: Beech wood samples at the end of termites' test

Figure 9 .

 9 Figure 9.14: Weight percent gain before (WPG) and after leaching (WPGL) for beech wood and pine wood samples at various concentrations of pyrolysis liquid

Fig.

  Fig.9.16 shows the weight loss after the correction factor test with their moisture content recorded at the end of the test. For the highest loading treatment, the weight loss recorded for the unleached samples in this test is similar or even higher than the weight loss caused by the leaching process (see Annex. B). For beech samples, the weight loss for the correction factor is (10.31 ± 0.56) % and for the leaching is (6.93 ± 0.48)%. Meanwhile, for pine samples, the weight loss for the correction factor and due to leaching is (8.40 ± 1.59)% and (6.18 ± 0.78)%, respectively. Such findings support the fact that the pyrolysis liquid is highly leachable when exposed to high moisture and humidity. Moreover, the relative humidity in the test media was known to be at approximately 90 %. It is also interesting to note that at the end of the test, the media which the samples had the highest loading of pyrolysis liquid were observed to have the darkest color, meaning that a high portion of products was leached out into the malt-agar medium (Fig.9.17).Following the results, the correction factor test is thus crucial to prevent the false-positive result on the weight loss caused by the fungal attack. Using the slow pyrolysis liquid from macadamia nutshell,[START_REF] Kartal | Efficacy of tar oil recovered during slow pyrolysis of macadamia nut shells[END_REF] previously reported that the weight losses due to the fungal attack in leached specimens were less than those observed in unleached specimens; still, they did not conduct the correction factor for the fungal test. In another study,[START_REF] Tomak | The combined effects of boron and oil heat treatment on the properties of beech and scots pine wood. part 2: Water absorption, compression strength, color changes, and decay resistance[END_REF] reported that when using treated wood with a high

Figure 9 .

 9 Figure 9.18: Microscopic observation of treated wood samples after leaching (a) tangential section treated with 100% concentration of pyrolysis liquid, and (b) radial section treated with 50% of radial section

Figure 9 .

 9 Figure 9.19: Weight loss of beech specimens and their moisture content after exposed to T. versicolor (WL is corrected with the correction factor)

  Figure 9.25: Beech wood samples treated with different concentration of pyrolysis liquid at the end of the termites' test

Figure 9 .

 9 Figure 9.26: Samples of pine at the end of termites' test (leached specimens)

  1.1 Cellulose, hemicellulose, and lignin in plant cell wall[START_REF] Wang | Pyrolysis of biomass[END_REF] .......................... 1.2 Basic monomer structure of cellulose (cellobiose unit) (Wang and Luo, 2016) .......................... 1.3 Main components of hemicellulose

Table 1 .

 1 3: Thermochemical conversion process[START_REF] Ronsse | Carbonization of biomass[END_REF]

		Torrefaction	Carbonization/ Slow pyrolysis	Fast pyrolysis Gasification
	Temperature <300 • C	>400 • C	∼500 • C6 00-1800 • C
	Heating rate	-	<80 • C/min	Up to 1000 • C/min	-
	Reaction time <2s	Hours∼days	Few seconds	-
	Medium	Oxygen-free	Oxygen-free or oxygen-limited	Oxygen-free	Oxygen-limited (air or steam/ oxygen)
	Solid yield	80%	35%	12%	10%
	Liquid yield	5%	30%	75%	5%
	Gas yield	15%	35%	13%	85%

Table 2 .

 2

	2: Summary of use classes and relevant attacking biological agents for wood and wood-based products
	according to standard EN 335 (2013)
	Use class	General use situation a	Disfiguring fungi	Occurrence of biological agents b Wood-destroying fungi Beetles Termites	Marine borers
	1I nterior, dry-	-	U	L	-
		Interior, or under cover,
	2	not exposed to the weather.	UU	U	L	-
		Possibility of water condensation
		Exterior, above ground,
		exposed to the weather.
	3	When sub-divided:	UU	U	L	-
		3.1 limited wetting conditions
		3.2 prolonged wetting conditions
	4	Exterior in ground contact and/or fresh water	UU	U	L	-
	5	Permanently or regularly submerged in salt water	U c	U c	U c	L c	U
	U = ubiquitous in Europe and EU territories
	L = locally present in Europe and EU territories

Table 2 .

 2 3: Biological activity of various slow pyrolysis liquid against wood-decaying fungi.

	Biomass	Temperature ( • C)	Main chemical constituents	Target organisms and (v/v) active concentrations	Reference
	Bark of P. abies and B. pendula, and fibre hemp (C. sativa)	275 and 350	Propionic acid; furfural; ethanol, acetic acid; hydroxymethylfurfural. methanol; formic acid;	C. puteana (1%), G. trabeum (1%). R. placenta (1%),	Barbero-López et al. (2019)
			Acetic acid; phenol;
	Oil palm trunk	350, 400, and 450	propanoic acid; 1-Hydroxy-2-propanone;	T. versicolor (1.5%), F. palustris (>1.5%).	Oramahi et al. (2018)
			3-Hydroxy-2-butanone.
	L. leucocephala,		Acetic acid; methanol;	T. versicolor,
	A. indica,		2-methylphenol; syringol;	R. amylospora
	E. camaldulensis,	400	4-propyl-2-methoxyphenol;	(6.25-12.50 mg/ml),	Theapparat et al. (2015)
	D. asper,		4-methyl-2-methoxyphenol;	G. trabeum
	H. brasiliensis.		4-ethyl-2-methoxyphenol.	(3.13-12.50 mg/ml).
	V. pubescens	350, 400, and 450	Acids and phenols.	T. versicolor (1.5%), F. palustris (>2%).	Oramahi and Yoshimura (2013)
			Phenol; O-Cresol; aromatic	T. versicolor (0.02%),
	Macadamia nutshell	-	hydrocarbons; hydrocarbons. 2,4 dimethylphenol;	P. ostreatus (0.01%), L. lepideus (0.20%),	Kartal et al. (2011)
			PAHs compounds.	T. palustris (0.20%).
			2,6-Dimethoxy phenol;
	Pistachio shell	500	2-Hydroxy phenol; 2-Methoxy phenol;	T. versicolor (50 mg/ml).	Okutucu et al. (2011)
			2-Methoxy-4-methyl-phenol.

Table 2 .

 2 4: Biological activity of various slow pyrolysis liquid against termites

	Biomass	Temperature ( • C)	Main chemical constituents	Target organisms and (v/v) active concentrations	Reference
			Acetic acid; phenol;
	Oil palm trunk	350, 400, and 450	propanoic acid; 1-Hydroxy-2-propanone;	C. formosanus (10%).	Oramahi et al. (2018)
			3-Hydroxy-2-butanone.
	V. pubescens	350, 400, and 450	Acids and phenols (detail chemical species are not identified).	C. formosanus (5%). (10%), R. speratus	Oramahi and Yoshimura (2013)
	Coconut shell	350-400	-	Odontotermes sp. (1:50).	Wititsiri (2011)
	Chips of C. japonica, P. menziesii, Q. serrata, and P. densiflora.	-	Acetic acid; phenol. propanoic acid; phenol; 2,6-dimethylphenols, 2-methoxy-4-ethyl-	R. speratus (0.1 mg/mL).	Yatagai et al. (2002)

Table 2

 2

	.5: Example of various study of bio-oil from slow and fast pyrolysis
	process for wood treatment
	Type of Pyrolysis Biomass	Reference
	Slow Pyrolysis	Giant cane	Temiz et al. (2013a)
	Slow Pyrolysis	Macadamia nut shell	Kartal et al. (2011)
	Slow Pyrolysis	Scots pine	Temiz et al. (2010)
	Slow Pyrolysis	Oil palm trunk	Lee et al. (2010)
	Fast Pyrolysis	Eucalypt wood	Lourençon et al. (2016)
	Fast Pyrolysis	Yellow poplar sawdust	Kim et al. (2012)
	Fast Pyrolysis	Oak and pine (wood and bark) Mohan et al. (2008)
	Fast Pyrolysis	Southern pine	Cooper et al. (2008)
	2.2.3.1 Pyrolysis liquid from slow pyrolysis
	Temiz et al. (

Table 5 .

 5 1: Proximate and ultimate analysis of sugarcane bagasse Characteristics Bagasse Ref. 1 a Ref. 2 b Ref. 3 c

	Proximate analysis (dry wt.%)
	-Moisture	8.5	15.4	6.0	5.4
	-Volatile matter (VM)	82.4	-	82.1	80.2
	-Ash content	4.2	3.1	1.6	3.1
	-Fixed carbon (FC)	13.4	-	16.3	11.3
	Fuel ratio (FC/VM)	0.16	-	0.20	0.14
	Ultimate analysis (dry wt.%)
	-Carbon (C)	47.3	50.2	49.6	44.8
	-Hydrogen (H)	5.7	5.6	6.0	5.8
	-Nitrogen (N)	0.4	1.1	0.5	0.2
	-Oxygen + Sulphur (O + S)	46.7	40.0	43.8	49.0
	Higher Heating Value (HHV; MJ/kg) 18.1	18.5	18.5	18.0

a Sugarcane bagasse obtained from South Africa

[START_REF] Carrier | Comparison of slow and vacuum pyrolysis of sugar cane bagasse[END_REF]

. b Sugarcane bagasse obtained from Florida, United States

[START_REF] Garcia-Perez | Sugarcane bagasse vacuum pyrolysis[END_REF]

. c Sugarcane bagasse obtained from India

Table 5 .

 5 2: Energy analysis of bagasse char and the yield of bagasse char and pyrolysis liquid Process condition Char yield (%) HHV a (MJ/kg) EY b (%) ED c Liquid yield (%)

	• C; 1 • C/min; 30 min 35.12 ± 0.96	27.44 ± 0.03	53.12	1.51 49.67 ± 0.28
	• C; 1 • C/min; 60 min 34.63 ± 0.20	27.41 ± 0.14	52.33	1.51 49.18 ± 1.33
	• C; 10 • C/min; 30 min 33.26 ± 0.60	27.20 ± 0.05	49.87	1.50 52.91 ± 0.60
	• C; 10 • C/min; 60 min 33.78 ± 0.60	26.86 ± 0.14	50.01	1.48 51.40 ± 1.12
	• C; 1 • C/min; 30 min 31.32 ± 0.25	28.52 ± 0.04	49.25	1.57 51.24 ± 0.71
	• C; 1 • C/min; 60 min 30.42 ± 0.31	28.67 ± 0.09	48.08	1.58 52.61 ± 0.95
	• C; 10 • C/min; 30 min 28.81 ± 0.19	27.81 ± 0.06	44.17	1.53 54.08 ± 0.50
	• C; 10 • C/min; 60 min 28.97 ± 0.36	27.85 ± 0.09	44.47	1.54 55.46 ± 0.22

a Higher Heating Value b Energy Yield c Energy Density

Table 5 .

 5 3: Coefficient of regression between pyrolysis parameters and the yield of bagasse char and pyrolysis liquid based on multivariate analysis Dependent variable Independent variable Estimate std. error t-value Pr (> |t|) R 2

		Intercept	52.883	1.182	44.726 3.10 × 10 -18
	Char Yield	Temperature Heating rate	-0.044 -0.186	0.002 0.028	-17.874 5.37 × 10 -12* -6.676 5.33 × 10 -6*	0.958
		Holding time	-0.003	0.008	-0.306 7.63 × 10 -1
		Intercept	38.611	2.112	18.280 3.81 × 10 -12
	Liquid Yield	Temperature Heating rate	0.026 0.309	0.004 0.050	5.861 6.242	2.41 × 10 -5* 1.18 × 10 -5*	0.821
		Holding time	0.005	0.015	0.314	7.58 × 10 -1

*

Correlation is significant at confidence level 0.05.

Table 5 .

 5 4: Proximate and ultimate analysis of bagasse char at different pyrolysis conditions

	Process conditions	Proximate analysis (wt.%) AR c (wt.%) VM a Ash FC b	Ultimate analysis (wt.%) CHNO	O/C H/C
	• C; • C/min; 30 min	25.67 ±1.15	10.79 ±0.12	63.54	86.63	69.50 ±0.14	3.81 ±0.03	0.5 ±0.03	26.14 0.28 0.66
	• C; • C/min; 60 min	24.31 ±0.58	11.72 ±0.78	63.97	88.81	70.23 ±0.90	3.66 ±0.04	0.58 ±0.05	25.53 0.27 0.63
	• C; • C/min; 30 min	25.80 ±0.06	12.81 ±0.26	61.39	95.86	70.35 ±0.07	3.32 ±0.00	0.65 ±0.02	25.68 0.27 0.57
	• C; • C/min; 60 min	24.56 ±0.54	13.1 ±0.51	62.29	97.91	69.40 ±0.42	3.46 ±0.07	0.62 ±0.01	26.52 0.29 0.60
	• C; • C/min; 30 min	14.33 ±0.21	13.00 ±0.85	72.67	87.80	73.53 ±0.40	3.07 ±0.00	0.53 ±0.04	22.87 0.23 0.50
	• C; • C/min; 60 min	13.01 ±0.31	13.99 ±0.49	73.01	94.99	75.70 ±0.00	3.08 ±0.04	0.61 ±0.00	20.61 0.20 0.49
	• C; • C/min; 30 min	16.01 ±0.36	15.50 ±0.79	68.50	98.58	72.90 ±0.57	2.74 ±0.03	0.62 ±0.03	23.74 0.24 0.45
	• C; • C/min; 60 min	16.43 ±0.06	13.07 ±0.57	70.50	84.52	71.95 ±0.78	2.85 ±0.01	0.57 ±0.06	24.63 0.26 0.48
	a Volatile Matter
	b Fixed Carbon
	c Ash Recovery

Table 5

 5

	.6: Main organic compound (%) presented in the organic fraction of
	pyrolysis liquid
	Compound name	Pyrolysis liquid (%) Classification 400 • C5 0 0 • C
	Acetic acid	8.48	7.22	Acid
	Glycolaldehyde	3.35	3.18	Aldehyde
	1-hydroxy-2-propanone	3.32	2.91	Ketone
	Methanol	2.28	1.90	Alcohol
	Levoglucosan	1.79	1.75	Sugar
	Formic acid	1.70	1.60	Acid
	Furfural	1.19	0.45	Furan
	1-acetyloxy-2-propanone	0.87	0.78	Ketone
	2-butanone,1-hydroxy-	0.82	0.73	Ketone
	2-hydroxy-2-cyclopenten-1-one	0.66	0.61	Ketone
	DGP *	0.63	0.52	Sugar
	Acetaldehyde	0.48	0.39	Aldehyde
	3-methyl-1,2-cyclopentanedione	0.41	0.38	Ketone
	Propionic acid	0.37	0.31	Acid
	Formaldehyde	0.33	0.26	Aldehyde
	2,6-dimethoxyphenol	0.30	0.27	Guaiacol
	2-methoxy-4-vinylphenol	0.24	0.18	Guaiacol
	Phenol-2-methoxy	0.22	0.20	Guaiacol
	Phenol	0.21	0.22	Phenol
	Phenol-2-methoxy-4-methyl	0.16	0.14	Guaiacol
	Phenol-4-ethyl-2-methoxy	0.15	0.12	Guaiacol
	Phenol-3-methyl+Phenol-4-methyl 0.11	0.11	Phenol

* DGP = 1,4:3,6-dianhydro-α-D-glucopyranose.

Table 7 .

 7

		1: Various drying temperatures used for wood treated with pyrolysis
	liquid products reported in different studies
	Pyrolysis type Temperature ( • C) Time	Biomass	References
	Slow	40	3 days	Macadamia nutshells Kartal et al. (2011)
	Slow	65	24 hours Giant cane	Temiz et al. (2013a)
	Slow	Ambient	3 weeks Pineapple waste	Yahayu et al. (2017)
	Fast	60	n/a	Eucalyptus fine	Lourençon et al. (2016)
	Fast	Air drying	24 hours Pinewood	Robinson et al. (2011)

Table 8 .

 8

	Visual rating Assessment
	0N o attack
	1A ttempted attack
	2S light attack
	3A verage attack
	4S trong attack

1: Assessment on the visual rating described in

the EN 117 (2013)

Table 9

 9

	.1: Number of termites in contact with paper during the 60 minutes of
	repellency test
	Treatment Concentration (%)	Number of termites in contact with paper Median Mean
	Control *	0 * 0 *	12 6	12.35 ± 4.24 (a) 6.40 ± 3.86 (b)
	Ethanol	0 * 01 7 2	13.89 ± 6.89 (a) 7.19 ± 7.41 (b)
		0 *	16	14.48 ± 5.07 (a)
		501.00 ± 0.00 (c)
	PL 400 • C	0 * 10	15 0	14.00 ± 5.17 (a) 1.00 ± 0.00 (c)
		0 *	13	12.70 ± 6.30 (a)
		20	0	1.00 ± 0.00 (c)
		0 *	13	12.77 ± 4.78 (a)
		512.96 ± 2.65 (c)
	PL 500 • C	0 * 10	16 0.5	13.75 ± 5.36 (a) 1.38 ± 0.49 (c)
		0 *	14.5	11.98 ± 7.11 (a)
		20	0	1.14 ± 0.38 (c)

* Paper treated with deionized water

Table 9 . 3

 93

: Compounds leached according to the GC-MS analysis Group Compounds Quantified compounds (mg/L)

Table 9 .

 9 4: Radial growth of C. puteana (CV) and T. versicolor (TV) in the medium of leachate products

	Fungi Samples	Radial growth (mm)

Table 9

 9

	.6: Weight loss of beech wood samples after the evaporation test and
	the leaching process
	Treatment	Weight loss (%)
	Evaporation 0.54 ± 0.06
	Leaching	7.29 ± 0.71

Table 9 .

 9 7: Performance of wood samples treated with pyrolysis liquid against termites before and after leaching

Table 9 .

 9 8: Performance of wood treated with pyrolysis liquid against termites (using beech samples from the correction factor test)

	Treatments	Weight loss (%) Survival rate (%)	01	Visual rating (%) 2 3
	BCF -5% leached	9.86 ± 2.91 (ab) 90.67 ± 3.06 (a)	0 0	0	0
	BCF -5% unleached	9.98 ± 0.90 (ab) 54.67 ± 11.02 (bc) 0 0	0	0
	BCF -10% leached	10.81 ± 0.86 (a) 86.67 ± 10.26 (a)	0 0	0	0
	BCF -10% unleached	9.89 ± 0.39 (ab) 64.67 ± 1.15 (abc) 0 0	0	0
	BCF -15% leached	9.97 ± 1.00 (ab) 82.67 ± 12.22 (ab) 0 0	0	0
	BCF -15% unleached	9.27 ± 0.39 (ab) 66.67 ± 9.24 (abc) 0 0	0	0
	BCF -20% leached	8.58 ± 0.46 (ab) 60.67 ± 14.05 (abc) 0 0	0	0
	BCF -20% unleached	7.94 ± 0.75 (ab) 61.33 ± 6.43 (abc) 0 0	0	0
	BCF -50% leached	6.84 ± 1.12 (bc) 38.67 ± 6.43 (c)	0 0	0	0
	BCF -50% unleached	3.94 ± 0.73 (cd) 4.00 ± 4.00 (d)	0 0	33.33 33.33 33.33
	BCF -100% leached	2.06 ± 0.29 (d) 0 (d)	0 100 0	0
	BCF -100% unleached	2.00 ± 0.96 (d) 0 (d)	0 100 0	0
	Control Beech 9.69 ± 1.12 (ab) 70.50 ± 15.70 (ab) 0 0	0	0

Table 2 :

 2 Evaporation test using beech samples

	Treatment	Retention (kg/m 3 )	IR (%)	WPG (%)	WLE (%)	ER (%)	WL decay (%) a,b	MC decay (%) b
	Beech-103 • C	743.03 ±21.95	119.53 ±7.28	33.33 ±1.98	0.54 ±0.06	2.16 ±0.23	0.66 ±0.41	85.80 ±3.68

a Corrected values b Virulence for T. versicolor (n = 12): WL = 38.83 ± 9.65; MC = 111.15 ± 39.65

Table 3 :

 3 Correction factor for the fungal test of the beech samples

	Treatment	Retention (kg/m 3 )	IR (%)	WPG (%)	WPGL (%) a	WLL (%) a	LR (%) a	WLCF (%)	MC (%)
	Beech-5%	23.35 ±1.31	73.64 ±7.75	2.41 ±0.17	1.09 ±0.22	1.28 ±0.24	59.96 ±7.74	L=-0.18 ± 0.87 U=0.76 ± 0.08	L=38.28 ± 14.89 U=55.57 ± 9.33
	Beech-10 %	48.53 ±2.75	78.32 ±8.52	4.19 ±0.37	1.93 ±0.48	2.11 ±0.23	54.27 ±8.83	L=0.10 ± 0.87 U=1.28 ± 0.43	L=39.27 ± 16.16 U=66.67 ± 10.39
	Beech-15 %	72.27 ±3.06	76.60 ±7.34	5.50 ±0.45	2.67 ±0.38	2.67 ±0.51	52.08 ±6.75	L=0.36 ± 0.41 U=1.49 ± 0.50	L=36.07 ± 9.54 U=77.31 ± 19.21
	Beech-20 %	95.61 ±3.83	76.76 ±6.54	6.81 ±0.47	3.29 ±0.43	3.33 ±0.21	53.00 ±4.33	L=0.58 ± 0.06 U=2.26 ± 0.27	L=34.26 ± 3.35 U=76.93 ± 9.34
	Beech-50 %	285.26 12.58	86.98 ±8.02	12.75 ±1.03	6.31 ±0.60	5.75 ±0.49	51.87 ±3.93	L=0.51 ± 0.46 U=4.80 ± 0.69	L=47.09 ± 10.84 U=74.46 ± 9.01
	Beech-100 %	747.28 ±28.71	118 ±10.51	34.28 ±2.52	23.94 ±1.06	6.93 ±0.48	28.75 ±0.94	L=3.74 ± 0.48 U=10.31 ± 0.56	L=68.92 ± 3.74 U=75.96 ± 4.08

a Corrected values

Table 4 :

 4 Correction factor for the fungal test of the pine samples

	Treatment	Retention (kg/m 3 )	IR (%)	WPG (%)	WPGL (%) a	WLL (%) a	LR (%) a	WLCF (%)	MC (%)
	Pine-5%	24.37 ±2.00	87.19 ±7.27	2.29 ±0.19	1.01 ±0.22	1.15 ±0.12	55.70 ±9.01	L=-1.82 ± 1.47 U=0.31 ± 0.61	L=70.91 ± 20.91 U=78.46 ± 18.66
	Pine-10 %	50.00 ±3.42	87.30 ±9.95	3.78 ±0.41	1.55 ±0.25	2.08 ±0.29	60.34 ±6.13	L=-1.14 ± 1.21 U=1.00 ± 0.19	L=63.78 ± 17.19 U=83.26 ± 15.44
	Pine-15 %	75.77 ±5.52	90.15 ±16.66	5.70 ±0.87	3.00 ±0.56	2.45 ±0.35	47.97 ±4.19	L=-0.12 ± 0.83 U=1.90 ± 0.30	L=60.78 ± 19.69 U=88.92 ± 8.87
	Pine-20 %	107.48 ±7.22	93.00 ±20.00	7.26 ±1.19	4.31 ±0.87	3.09 ±0.54	44.30 ±4.02	L=-0.24 ± 0.81 U=2.25 ± 0.31	L=66.12 ± 11.48 U=88.44 ± 3.46
	Pine-50 %	304.54 ±13.65	108.00 ±17.20	15.13 ±1.97	8.09 ±1.75	5.91 ±0.44	47.04 ±4.66	L=-0.23 ± 0.60 U=5.67 ± 0.80	L=88.35 ± 8.20 U=97.64 ± 10.45
	Pine-100 %	594.71 ±124.20	101.28 ±23.50	27.46 ±5.93	18.91 ±4.84	6.18 ±0.78	30.96 ±1.94	L=2.57 ± 0.54 U=8.40 ± 1.59	L=74.42 ± 8.72 U=82.69 ± 2.49

a Corrected values

Table 5 :

 5 Beech samples treated with pyrolysis liquid at different concentrations, exposed to T. versicolor Virulence for T. versicolor (n = 20): WL = 26.28 ± 8.76 ; MC = 82.01 ± 24.21

	Treatment	Retention (kg/m 3 )	IR (%)	WPG (%)	WPGL (%) a	WLL (%) a	LR (%) a	WL decay (%) a,b	MC decay (%) b
	Beech-TV	23.28	69.38	2.25	0.72	1.53	69.97	L=16.44 ± 10.80	L=64.73 ± 24.39
	5%	±1.40	±8.02	±0.21	±0.22	±0.24	±8.19	U=24.47 ± 5.93	U=91.72 ± 23.33
	Beech-TV	46.13	69.38	3.80	1.20	2.31	68.25	L=21.21 ± 9.25	L=77.18 ± 15.21
	10 %	±2.65	±8.65	±0.36	±0.40	±0.67	±10.23	U=19.89 ± 8.80	U=120.99 ± 18.52
	Beech-TV	75.06	74.03	5.51	2.22	3.03	60.41	L=11.22 ± 9.18	L=52.04 ± 8.65
	15 %	±4.47	±8.87	±0.59	±0.37	±0.57	±4.68	U=10.25 ± 3.95	U=107.1 ± 12.50
	Beech-TV	103.52	81.03	7.24	2.61	4.03	63.08	L=29.79 ± 10.25	L=85.81 ± 18.97
	20 %	±2.85	±5.18	±0.53	±0.53	±0.42	±6.64	U=14.42 ± 6.46	U=130.48 ± 14.09
	Beech-TV	294.26	91.13	15.42	9.08	5.30	41.45	L=3.52 ± 2.49	L=87.35 ± 7.89
	50 %	±21.39	±13.75	±2.01	±1.37	±0.63	±4.34	U=2.56 ± 0.95	U=98.19 ± 17.70
	Beech-TV	737.25	115.74	34.07	23.29	7.65	31.48	L=2.27 ± 0.29	L=84.92 ± 4.23
	100 %	±22.67	±6.02	±1.56	±2.01	±0.75	±3.51	U=2.33 ± 0.34	U=84.84 ± 4.67

a Corrected values b

Table 6 :

 6 Pine samples treated with pyrolysis liquid at different concentrations, exposed to C. puteana Virulence for C. puteana (n = 19): WL = 41.87 ± 11.48 ; MC = 89.23 ± 18.99

	Treatment	Retention (kg/m 3 )	IR (%)	WPG (%)	WPGL (%) a	WLL (%) a	LR (%) a	WL decay (%) a,b	MC decay (%) b
	Pine-CP	23.32	81.56	2.29	0.80	1.39	66.32	L=32.96 ± 6.92	L=68.06 ± 9.44
	5%	±3.22	±19.96	±0.51	±0.40	±0.44	±15.94	U=32.48 ± 10.98	U=64.49 ± 12.65
	Pine-CP	50.44	79.19	4.14	1.73	2.41	60.90	L=27.79 ± 16.15	L=83.88 ± 22.30
	10 %	±3.34	±12.71	±0.54	±0.31	±0.71	±6.56	U=9.51 ± 9.84	U=86.37 ± 27.00
	Pine-CP	83.20	92.10	6.34	2.44	3.56	63.09	L=24.40 ± 15.80	L=105.09 ± 21.25
	15 %	±4.67	±15.37	±0.96	±0.66	±0.55	±6.47	U=4.96 ± 2.39	U=117.55 ± 14.58
	Pine-CP	106.65	90.10	7.62	3.51	3.83	54.97	L=21.74 ± 11.21	L=65.06 ± 19.66
	20 %	±10.97	±14.74	±0.89	±0.16	±0.91	±3.52	U=6.22 ± 4.16	U=97.27 ± 30.50
	Pine-CP	275.82	90.45	14.20	7.78	5.26	45.38	L=14.31 ± 14.24	L=80.98 ± 25.17
	50 %	±16.87	±8.26	±1.16	±0.83	±0.44	±1.52	U=2.72 ± 0.30	U=107.66 ± 9.86
	Pine-CP	657.49	105.06	30.47	20.70	6.21	30.05	L=2.45 ± 0.55	L=82.79 ± 6.49
	100 %	±89.87	±18.36	±5.24	±4.03	±0.59	±2.12	U=2.89 ± 1.51	U=77.96 ± 4.97

a Corrected values b

Table 7 :

 7 Pine samples treated with pyrolysis liquid at different concentrations, exposed to R. placenta Virulence for R. placenta (n = 19 ): WL = 47.53 ± 15.40; MC = 161.21 ± 37.74

	Treatment	Retention (kg/m 3 )	IR (%)	WPG (%)	WPGL (%) a	WLL (%) a	LR (%) a	WL decay (%) a,b	MC decay (%) b
	Pine-RP	22.41	70.44	2.26	1.19	0.98	52.48	L=27.30 ± 18.73	L=121.26 ± 23.71
	5%	±2.54	±11.17	±0.25	±0.12	±0.16	±7.33	U=25.86 ± 16.17	U=130.31 ± 23.65
	Pine-RP	52.78	89.73	4.46	1.53	2.64	63.94	L=37.63 ± 17.38	L=131.48 ± 24.77
	10 %	±5.06	±22.64	±0.84	±0.30	±0.62	±6.83	U=42.25 ± 4.06	U=131.65 ± 10.31
	Pine-RP	82.62	93.92	6.54	3.12	3.42	54.05	L=34.36 ± 17.56	L=135.50 ± 26.30
	15 %	±5.41	±16.58	±0.83	±0.61	±0.43	±6.00	U=17.01 ± 17.12	U=121.41 ± 25.04
	Pine-RP	106.83	91.66	7.73	3.53	3.77	54.24	L=26.38 ± 21.39	L=121.56 ± 25.18
	20 %	±10.89	±19.34	±1.32	±0.92	±0.74	±5.16	U=15.10 ± 11.67	U=113.68 ± 15.05
	Pine-RP	255.11	85.90	13.78	7.71	5.18	44.91	L=23.12 ± 11.26	L=115.21 ± 14.40
	50 %	±33.71	±18.61	±2.46	±2.12	±0.96	±3.67	U=6.22 ± 1.89	U=109.69 ± 12.63
	Pine-RP	682.87	116.89	33.13	20.55	7.70	7.70	L=2.15 ± 0.87	L=78.85 ± 15.40
	100 %	±65.72	±26.52	±6.50	±3.76	±1.39	±1.39	U=4.91 ± 1.01	U=97.54 ± 17.80

a Corrected values b

Treating the pyrolysis liquid into the wood samples to investigate its potential for wood protection, determine the optimum drying temperature, analyze its leaching properties, and obtain the effective concentration threshold against fungi and termites.

Acknowledgment

Firstly, I would like to express my gratitude to the Indonesia Endowment Fund for Education, Ministry of Finance, Republic of Indonesia, for awarding me the doctoral scholarship so that this thesis could come to fruition.

Next, I'd like to thank you sincerely for my thesis director, Mériem Fournier, who had been very supportive in the realization of this thesis work. Sincere gratitude also goes to my thesis co-director, Marie-France Thévenon, who was also my principal supervisor, who had welcomed me to her lab and given me so much advice and supervision. I also greatly appreciate my supervisors in CIRAD, Jean-Michel Commandré, and Kévin Candelier, for their inputs and help throughout my research work.

I would like to thank

Publications and Award

Publications