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Social War (91–87 BC)

The Social War (from Latin bellum sociale, "war of the allies"), also called the Italian War or the Marsic War, was fought largely from 91 to 88 BC between the Roman Republic and several of its autonomous allies (socii) in Italy. Some of the allies held out until 87 BC.

The war started in late 91 BC, with the rebellion of Asculum. Other Italian towns quickly declared for the rebels and the Roman response was initially confused. By the new year, the Romans had levied huge armies to crush the rebels but found initial headway difficult; by the end of the year, however, they were able to cut the Italian rebels into two, isolating them into northern and southern sectors. The Italian rebels attempted to invade Etruria and Umbria at the start of 89 BC but were defeated. In the south, they were defeated by Lucius Cornelius Sulla, who for his victories would win a consulship the next year. The Romans retained the initiative and by 88 BC, the conflict was largely over and Roman attention had been captured by the ongoing First Mithridatic War. The few Italian rebels on the field by 87 BC eventually reached a negotiated settlement during a short civil war that year. At various stages of the war, Romans brought legislation allowing Italian towns to elect Roman citizenship if they had not revolted or would otherwise put down arms, draining support from the rebels.

Views differ as to the causes of the war, primarily on whether Roman citizenship was already a coveted status whose extension was the goal of the Social War or not. The main ancient source for the period is the relatively late Appian, who wrote in the imperial period during the 2nd century AD, and whose narrative is largely one based on demands of the allies for Roman citizenship. Other historians, most especially Henrik Mouritsen, have focused instead on a perceived alternative tradition which has the Italian allies rebelling against Roman hegemony and encroachment on allied lands.

The massive expansion of the citizenship that followed the Social War remained a politically-charged topic, especially in terms of how they would be allocated into voting blocks. Disputes over enfranchisement played a role in Sulla's march on Rome in 88 BC to depose plebeian tribune Publius Sulpicius Rufus. Fears of Sulla rolling back hard-won Italian rights contributed to resistance during Sulla's civil war. The conflict also blurred the distinction between Romans and their enemies; the presence of large armies in Italy during the war also provided opportunities for generals to seize power extralegally. For these reasons and others, some historians believe the conflict played an important role in setting up the collapse of the republic.

Name
The name Social war is an improper English translation of bellum sociale, which means "war of the allies" (from Latin socius, meaning "ally"). Today, the name is used more generally in classics scholarship to refer to any war between allies. The name bellum sociale was first used in the second century AD by the historian Florus, and only became common during the imperial period. The Romans of the time called it the Marsic war named for the Marsi, an Italian tribe located east of Rome who during the war killed two Roman consuls, or otherwise called it the Italian war. The focus on the Marsi may also have to do with Quintus Poppaedius Silo, who was one of the Italian leaders.

Usage in the late republican and early imperial period treated the names Marsic and Italian war as largely interchangeable. Cicero's works refer to it as bellum Marsicum or bellum Italicum (though he also uses bella cum sociis); Sallust, according to Aulus Gellius, calls it the Marsic war; Velleius Paterculus, Asconius Pedianus, and Julius Obsequens call it the bellum Italicum. An official senatus consultum dated to 22 May 78 BC calls it bellum Italicum and the Augustan-era fasti consulares call it bellum Marsicum.

Italy in the second century
The Italian peninsula during the second century BC was dominated by the Roman Republic, which was allied in a collection of bilateral treaties with the many city-states on the peninsula. In general, those cities received guarantees of territorial integrity and internal self-government in exchange for supporting Rome with men during its many wars. Allied contingents made up an increasing portion of Roman manpower: by 295 BC, the allied contingents of Roman-led armies as a whole outnumbered the Romans on the field and, by 218 BC, there were three allies on the field for every two Romans. This made allied manpower indispensable for Roman military superiority.

Cities cooperated with Rome for various reasons. They received shares of the war spoils and land assignments. Rome also supported allied elites against popular revolts (eg at Arretium, Lucania, and Volsinii in 302, 296, and 264 BC, respectively). While some of the cities defected during the Second Punic war after the Battle of Cannae in 216 BC, the defectors were defeated and harsh terms applied. Over time, the Romans started to interfere in the internal affairs of their allies, though historians differ as to its extent. For example, when the senate acted to suppress the Bacchanalia in 186 BC, historians differ as to whether this applied only to Roman land or was extended extraterritorially to the allies.

By the Social war, the allies were mainly located in the following regions: two northern ones (Etruria and Umbria) and more further south (Lucania, Apulia, and Magna Graecia). As far back as the fifth century, the Oscan and Umbrian-speaking communities in southern Italy had formed a flexible confederal league; the most powerful of these were the Samnites and Lucanians. The Romans had fought with the Samnites a number of wars during the conquest of Italy; even afterwards, these allies retained their cohesiveness, having defected from Rome as a single bloc during the Second Punic war. Romanisation through to the second century proceeded with considerable heterogeneity: in Apulia and Samnium, Latin influence was largely absent in both the archaeological and literary sources, while in Marsic lands inscriptions indicate adoption of the Latin alphabet. On the whole, Italian tribes and peoples on the eve of the Social war still held themselves distinct from Rome, just as they had in previous centuries.

Also importantly, before the 1st century AD, it was not possible for a person to hold more than one citizenship. Nor, before the empire, were allied soldiers granted Roman citizenship at the close of their service. For example, Cicero deliberately contrasts Italic single citizenship against Greek multiple citizenship in his speech for Lucius Cornelius Balbus, a provincial who had been granted citizenship by Pompey. Citizenship was linked to territories: a person who received Roman citizenship gave up their local citizenship; losing local citizenship and living outside of Roman territory meant a local reduction in socio-economic status.

Italian demands
The "Italian question" refers to the relationship between Rome and her Italian allies. It is still not entirely clear what the Italian allies were fighting for. There are two threads in the ancient accounts: one depicting the struggle as one for Roman citizenship and another as one against Roman domination.

Edward Bispham, writing in the 2016 Companion to Roman Italy, concludes that "it seems certain that the Social War is best understood as a revolt from Rome" but synthesises the approaches in that the desires for citizenship and independence are themselves expressions of an underlying desire for equality and freedom, inside or outside the Roman political system.

Desire for citizenship
Appian's Civil Wars is the main source for much of this period. It provides three themes for the Italians: support for agrarian reform, votes for land, and demands for political equality. According to Appian, the agrarian reforms of Tiberius Gracchus were meant to support the Italians. However, there is no good evidence to verify this claim and most historians reject it as a political tactic either to distinguish between free and slave or as an anachronism interjected by his brother Gaius to legitimate Gaius' reform agenda some ten years later. Attempts to actually grant citizenship started in 125 BC with a proposal by Marcus Fulvius Flaccus. Gaius Gracchus is said to have brought similar proposals. These attempts were largely brought because Roman tribunes and magistrates believed that granting citizenship could be traded for Italian elites acquiescing over occupied public lands.

Appian similarly frames the war as a reaction to the failed reform proposals of the plebeian tribune of 91 BC, Marcus Livius Drusus. As part of a complex scheme to change criminal court jury composition, Drusus allegedly would have to seduce the people with free land, which required public lands, which required pushing Italians off that land, which required a sweetener of citizenship to quell objections. When the proposals failed, the Italians went to war to secure the citizenship and legal equality denied to them in peace.

The most convincing theme which Appian presents, however, is an Italian desire for political equality: he says the Italians aspired to be "partners in rule rather than subjects". However, it is likely that poor and rich Italians sought different goals: poorer Italians were likely seeking freedom from unfair treatment by Roman magistrates; it would have been their richer compatriots that would benefit from direct access to Roman politics.

More modern versions of the citizenship thesis have been advanced by Emilio Gabba, arguing that Italian commercial classes (the publicani) drove romanisation in an attempt to share in the rewards of empire. The exalted position of Italian businessmen in the provinces may have reinforced their status inferiority at home; combined with a desire to influence Roman provincial policy, they may have sought to secure their business rights by becoming Roman citizens. This thesis, however, is not widely accepted since the Italians who were most exposed to the Greek East were not those who led the revolt and had to be coerced into joining it. Similarly, A N Sherwin-White believed that the Italians wanted Roman citizenship to secure legal equality. Less convincingly, D B Nagle argued that economic factors could explain the start of the war.

Rebellion

Henrik Mouritsen, in the influential 1998 book Italian unification, argues that Appian's citizenship narrative is highly anachronistic. For writers in the imperial period, Roman citizenship was highly desirable. Those writers then retrojected that desirability onto the Italians who lived centuries before their time. His analysis of the evidence also concludes that before the Social war, there was little agitation for citizenship, multiple citizenships still being invalid, which would have been incompatible with local autonomy. As to the possibility of votes for land, he writes "Flaccus' citizenship bill [and bills similar to it] would have been infinitely more far-reaching in its implications than the reform promoted... it would lead to a total upheaval of the traditional alliance system on which Roman domination in Italy had been based for centuries... as an attempt to restart the land distribution process the bill would probably have been of scant value". The extent of the upheaval of the alliance system similarly leads Mouritsen to reject granting citizenship as part of Drusus' attempt to change jury composition as means far in excess of the ends sought.

Instead, Mouritsen focuses on Italian discontent with Roman public land reform. Rome's public lands had been won centuries prior to the 90s BC when the nascent republic had subjugated the Italian peninsula. Newer lands had also been forcibly taken from southern Italian cities that had sided with Hannibal during the Second Punic War. With each victory, the Romans demanded and received from the Italians a latent title to lands the Italians still occupied. For centuries, Roman claims on those lands were unenforced. After the start of the land reform process in 133 BC with Tiberius Gracchus's lex Sempronia, Italians started to complain about Roman magistrates illegally encroaching on their land holdings; in 129 BC, the senate acted and deprived the land redistribution commission of its survey jurisdiction, putting a pause on land distributions. The commission, before the pause in 129 BC, likely quickly surveyed and parceled out the unoccupied and recently surveyed Hannibalic war-era lands. The older holdings elsewhere, however, were impossible to disentangle from private lands. Never surveyed and with unclear borders, Italians objected to the land commission's infringements on their property, which was guaranteed by treaty. The objections brought the redistributive process quickly to a halt.

Mouritsen proposed instead the following reconstruction for the start of the war in the late 90s BC. Drusus, seeking to placate the plebs in exchange for a change in the jury courts, proposed a law to do more widespread land distributions against the allies' protests. Their anger increased when the law passed over their objections and Rome started seizing allied lands; the allies therefore started preparations for an insurrection by late summer 91 BC. Amid this distrust, Drusus was blamed for breaking down relations with the allies, which led to a confrontation between Drusus and the consul, Lucius Marcius Philippus, in the senate some time in September. Rome responded to these rumours of Italian unrest by sending garrison forces into Italy, which explains their capture at the start of the war. Drusus may have then attempted to rescue his standing and placate the allies by trying to pass a law to give the allies citizenship. After this attempt failed amid Drusus' declining popularity, the attempts of the Latins – who actually were agitating for citizenship – to assassinate the consuls, who opposed Latin citizenship, at the Latin Festival became known. With the prospect of the Latins deserting Rome, the balance of military power would shift into the Italians' favour. After secret negotiations, the Italians then launched their bid to throw off Roman hegemony.

Preparations
As evidenced by the destruction of Fregellae after an attempted revolt in 125 BC, it was an enormous risk to rebel against Rome. The Italians, in planning their war, would have to form reliable alliances secured with hostages. Appian describes a long series of secret negotiations between the Italian states, of which Rome was ignorant.

The Romans were likely aware of some kind of unrest, even if they did not know of its scope. This is evidenced by Roman garrisons being captured at the start of the war in unfriendly cities. It is likely those garrisons had been dispatched before the start of the war to strategically important locations. Already by late 91 BC, the Romans had sent praetors with levied troops around the peninsula to investigate rumours of a plot. But by the time the investigations completed (or as a result of those investigations), the war had started. Regardless, preparations for a revolt likely were brewing before Drusus' tribunate in 91 BC.

Military command
At the outbreak of the war, the Italians levied forces and formed up armies to oppose the Romans. To have done this so quickly, agreements must have been reached on power-sharing and command before the outbreak of the war.

According to Photius' summary of Diodorus Siculus, which is accepted by most modern scholars, the Italians established at Corfinium a new capital with a forum and five-hundred-man senate. The senate then appointed two consuls and twelve praetors, dividing them evenly between northern and southern fronts (with Italian consuls Quintus Poppaedius Silo and Gaius Papius Mutilus assigned to the north and south, respectively). Reconstructions have differed over the Italian state's organisation. Theodor Mommsen in 1854 proposed that the Italians self-organised basically along the same lines as the Romans. Alfred von Domaszewski in 1924 suggested that Silo and Mutilus were merely leaders of two major factions in the Italian forces and that the twelve "praetors" reflected twelve tribal divisions arranged in a federal structure; this position was accepted in the first edition of the Cambridge Ancient History in 1932. Later reconstructions have interjected popular elements à la the Roman comitia centuriata. But others, such as Mouritsen, have taken a more critical eye at the evidence and viewed the Italian magistrates and senate as a more formally federal structure without direct popular involvement.

Mouritsen reads from Livy's description of the Latin War (when Rome's Latin allies rebelled c. 340 BC) possible hints for the lost portions of Livy's narrative on the Social War. Because much of Livy's work on early history have long been recognised to be anachronistic, Mouritsen believes that the narrative on the Latin War may anachronistically reflect Social War-era realities. In the Livian Latin War, the Latin allies demanded a real power-sharing arrangement where magistracies and senatorial seats were to be set aside for the Latins in proportion to military contributions. If the Italians had similar aims in 91 BC, they would have been incompatible with a centralised Roman state and the supremacy of Rome's urban elite.

However, beyond Diodorus' summarised description of the Italian government, there few other sources which describe the Italian coalition's internal politics or offices. Instead, they refer to various tribal and ethnic leaders without distinction of office. Florus, for example, mentions no Italian senate or magistrates, but instead says that the Italians served each under their own standards. Coinage, along with Livy, seem to refer to a number of imperatores (Oscan embratur), which may have been appointed by each ethnic group. They did not seem to have been replaced after death in battle, implying the lack of any Italian elections. Christopher Dart suggests that the Italians converted the victory title imperator into an official magisterial title, in the same way imperator later turned into the title of the Roman emperor in the Flavian era.

Inciting incident
In late 91 or early 90 BC, a rumour was heard that Asculum was exchanging hostages with another city. Such an exchange was customary in the preparations for war to prevent allied cities from defecting. A Roman praetor by the name of Quintus Servilius, possibly the quaestor of 103 BC, rushed to the city and threatened violence if Asculum did not desist. The inhabitants, however, fearful of Roman discovery, responded by killing the praetor and his legate Fonteius. They then killed all the Romans in the city and ransacked their goods. Violence having been committed against the Romans openly, the Italians revolted as one.

This sequence is at odds with Appian's account, which paints Asculum as rioting in late 91 BC in response to Marcus Livius Drusus' assassination in Rome and Roman prosecution of Italian allies. In this narrative, Drusus, whose political star was waning since the death of his influential supporter Lucius Licinius Crassus, had his legislation invalidated by the senate. He was shortly thereafter killed by an unknown assassin. Around this time, the Italians send a delegation to Rome but the Romans refuse to negotiate. Appian asserts that after Drusus' death but before the start of the war, the equites set up the quaestio Varia (the Varian court) to prosecute those who aided the Italians secure citizenship. After the double blow of Drusus' death and the prosecution of their allies at Rome, Appian then has the Italians form their conspiracy and revolt. However, as the Italians could not have had enough time between Drusus' death and the start of the war to organise, Appian's timing cannot be correct.

Course
While the inciting incident of the war is clear, its end is not. One could argue various dates, ranging from 89 BC, when most of the fighting was practically complete, down to November 82 BC and the Battle of the Colline Gate when an identifiably Italian group of rebels was at last defeated. This article presents events down to the nominal pacification of the Samnites and Lucanians in 87 BC.

The main sources for the course of the war are relatively confused. Appian's account present events roughly geographically, producing a confusing non-chronological account. Livy's summaries indicate that Livy wrote chronologically, but the details of the original Livian volumes are lost. Other sources such as Diodorus (via Photius), Florus, and Velleius Paterclus recount events non-chronologically. There were two main theatres of the war, with one in the north and one in the south. There also was an abortive attempt to incite rebellion in Etruria and Umbria, but the Romans moved quickly and brutally to suppress it. The northern theatre was centred on Asculum (in the lands of the Piceni and Marsi) with the southern theatre in Samnium, Lucania, Apulia, and Campania.

The immediate reaction in Rome to the rebellion was one of confusion. After the war's start, Quintus Varius Hybrida, then a plebeian tribune, set up a permanent court searching around for conspirators who incited the Italians to war. Mouritsen writes of the court, "such stab-in-the-back theories are plausible only when no other explanation is at hand; apparently the Romans did not see any direct connection between the franchise question and the outbreak of the war". It is possible that in the early winter of 90 BC there was an abortive attempt to negotiate a peace before fighting started; if it occurred, the senate refused to negotiate.

90 BC

Appian reports that the Italians at the start of the war mobilised some 100,000 men. Rome's Latin allies remained loyal. Rome also continued to control Capua and central Campania, which proved logistically vital. The consuls of the year, elected in a time of relative peace, were Lucius Julius Caesar and Publius Rutilius Lupus. The two men had access to experienced legates: Gaius Marius and Lucius Cornelius Sulla.

Initial offensive
The Romans levied a massive force over the winter, allowing the consuls of 90 BC to depart for war immediately. All consuls and praetors that year were assigned to Italy; the provincial governors at the start of the war had their terms continuously prorogued. According to the summary of Livy, Livy included tables of the Latin and foreign communities that sent auxiliaries to join the Romans. Modern estimates of Roman manpower exceed 140,000, split between fourteen legions (two for each consul and one each for ten legates). Rome also conscripted ships and mercenaries from its overseas allies; two triremes, for example, were taken from Heraclea Pontica on the Black Sea and returned eleven years later.

The initial Italian offensive struck in late 91 and early 90 BC. It was clearly planned with full knowledge of typical Roman strategy and operations. There was a policy of mercy toward pro-Roman combatants in the southern theatre commanded by Gaius Papius Mutilus; the war also assumed a "distinctive character" in the extent to which Roman soldiers defected to the Italians. For example, when Nola was captured, the Italians were able to induce the defection of most of the Roman soldiers (the officers refused and were starved to death).

In the initial offensive, the colony of Aesernia was put under prolonged siege: the consul Lucius Julius Caesar moved to break it but was unsuccessful; the Romans suffered further reverses, losing Venafrum, Grumentum in Lucania, and suffering defeat near Alba Fucens. The most important victories for the Italians were in Campania and Picenum. In Campania, Mutilus took Nola, Herculaneum, and Salernum, before being stopped at Acerrae from advancing on Capua. In Picenum, Gaius Vidacilius, Titus Lafrenius, and one Publius Ventidius defeated Gnaeus Pompeius Strabo and forced him into Firmum. Vidacilius took the opportunity then to advance into down the eastern Italian coast into Apulia, taking Canusium. Aesernia fell later in the year after repeated failures by Lucius Julius Caesar to relieve the town; turning south, Caesar attempted to stop Mutilius from forcing the fortress at Acerrae, but both sides found themselves in a series of indecisive engagements.

Roman breakout

While attempting to lead his men across a river in the northern theatre on 11 June, the consul Publius Rutilius Lupus fell in the Battle of the Tolenus River while fighting against the Marsi when his undertrained men were routed during the crossing. After this battle, when the huge number of bodies returned to Rome caused a panic, the senate decreed that war dead should in the future be buried on the field. In this same engagement, Gaius Marius, another of Rutilius' legates and hero of the Cimbric wars, was able to pull off a decisive victory by forcing the river when alerted to the disaster by the bodies that flowed downstream; he eventually assumed command after Rutilius' replacement was assassinated at false surrender negotiations. Marius, assisted by a flanking manoeuvre by Lucius Cornelius Sulla, then inflicted a victory over the Marsi near the Fucine lake, which split the Italians in two.

Sextus Julius Caesar, consul in 91 BC and promagistrate this year, moved to relieve Firmum some time in October. Between Sextus' army and Pompey Strabo's forces, Labrenius' forces were routed and forced into Asculum, which was then besieged by Strabo. Sextus' forces then forced back Vidacilius into Apulia and placed it too under siege in December. The northern front of the war largely collapsed after these victories. Attempts to incite rebellion in Etruria and Umbria could have opened a third front against Rome, but were quickly suppressed; Appian notes also that the senate acceded to garrisoning Cumae with freedmen, recruited into the army for the first time.

With a collapsing northern front and the division of the Italians into two, Italian defeat became largely inevitable. The Italians attempted opening negotiations, inviting Mithridates VI Eupator of Pontus to invade, but Mithridates responded equivocally. As Rome started to gain the upper hand, the senate decreed some time around October that consul Lucius Julius Caesar should bring legislation allowing any Italian community that had not revolted or otherwise promptly laid down their arms to elect Roman citizenship. This was passed and became the lex Julia de civitate; it also removed one of the main causes of the war – be it demands for citizenship or for security of land holdings – and provided that new tribes would be created for new citizens. Between the citizenship law and the costs of the war, only the Italian hard-liners remained in the field.

89 BC
The new consuls for 89 BC were Gnaeus Pompeius Strabo and Lucius Porcius Cato. In January, the Marsi attempted to support the rebellions in Etruria and Umbria. The two consuls moved to intercept the Marsi, who were commanded by Titus Vettius Scato. Strabo defeated the Marsi near Asculum, forcing them into retreat across the snowy mountains. Cato, taking command from Marius, defeated the Marsi near the Fucine lake, but was himself killed in battle. It is likely that Cato was killed early in the year, leaving only Strabo as consul for the remainder of 89.

The Romans continued on the offensive against the Marsi, under the command of legates Lucius Cornelius Cinna and Marcus Caecilius Cornutus, and forced the Marsi to petition for peace. These victories allowed the Romans a free hand in the siege of Asculum and freedom to attack into southern theatre from the north. Corfinium was also taken, forcing the Italians to transfer their capital to Bovianum. The Romans also subjugated the Vestini and the Marrucini. By summer, the Romans had pacified the northern theatre, except for Asculum, which was still under siege.

Rome also took the offensive in the south. Sulla, commanding an army and supported by a fleet, besieged Nola and took Pompeii, defeating an attempt to relieve the cities by Lucius Cluentius. After the capture of Pompeii, Sulla quickly took Stabiae and Herculaneum by June. Sulla then moved into Samnium, subjugating the Hirpini and giving gentle terms, before taking Bovianum by September after a bitter struggle, forcing the Italians to move their capital again to Aesernia (now under their full control). That year, Sulla stood for and won the consulship of 88 BC, with Quintus Pompeius Rufus as his colleague.

Asculum surrendered in November 89 BC after its commander, Vidacilius, committed suicide. For this victory, Pompey Strabo celebrated a triumph on 25 December over Asculum and Picenum. Strabo, however, infamously refused to give any of the plunder to the state, even though the public treasury was empty. Further legislation was enacted to extend the citizenship with the passage of the lex Plautia Papiria (though the Samnites and Lucanians, still under arms, were excepted). New legislation was also brought by Pompey Strabo to incorporate new colonies in Transpadane Gaul with Latin rights. The reorganisation of Italy also required the formation of new municipia as well as surveying of their lands and establishment of their charters. This longer process would continue until the age of Caesar.

88 and 87 BC

By 88 BC, the war was largely over, except for some isolated holdouts. Elections for the consulship of 88 were delayed by Pompey Strabo's late return to the city, but eventually returned Lucius Cornelius Sulla and Quintus Pompeius Rufus. The senate, troubled by news of Mithridates VI Eupator's invasion of Asia in the east, assigned neither consul to commands against the Italians; Sulla by lot was assigned the command against Mithridates.

Early in the year, Pompey Strabo's command in the northern theatre was prorogued and he quickly accepted the surrender of multiple Italian towns and communities, putting an effective end to the war in the north. The remaining northern insurgents fled south to Samnium and Apulia, where the Italians still controlled large tracts of territory. The Italians reorganised around Quintus Poppaedius Silo and designated him supreme commander; according to Diodorus, Silo command a force of some 50,000 men, which would have been hopelessly insufficient to fight the Romans. Regardless, Silo was able to reverse Roman advances in Samnium and also recapture Bovianum. He then crossed the Apennines and engaged Quintus Caecilius Metellus Pius in Apulia, where his forces were badly defeated and Silo was killed.

Following Silo's death, Italian organised resistance collapsed. For Livy and Appian, his death marks the end of the Social war. However, a remnant of Samnite and Lucanian rebels fought on in Bruttium and even sent appeals to Mithridates of Pontus for an intervention in Italy. Faced with death or slavery, they refused to surrender. Late in 88 or in 87, after Sulla's departure for the east, this rebel force unsuccessfully attacked Isiae and Rhegium near the Strait of Messina. The outbreak of a short civil war at Rome in 87 BC allowed them to nonetheless reach a negotiated settlement with the weakened Roman government; the rebels sided with the faction of Lucius Cornelius Cinna and Gaius Marius after being promised citizenship, the return of hostages and deserters and the return of all loot taken by the Romans.

Impact
Even in ancient times the conflict was perplexing and the final outcome of the war or its immediate impacts were not entirely clear. One can interpret the terms under which the various Italian communities at different times reached with the Roman state as victory for either Italians or Romans or alternatively as a negotiated stalemate.

Economic and legal

The war was a "supreme effort" on both sides. For example, Appian reports the need for soldiers was so great that freedmen were for the first time inducted into the army. Edward Bispham, in a Companion to Roman Italy, notes that the republic "never minted more silver denarii than during the conflict", indicating the financial strain imposed on the Roman state in supplying and paying for an unprecedented number of troops. Devastation of the war in the central and southern portions of Italy was "profound". Archaeological evidence points towards the Social war, along with the following Sullan civil war, devastating the central Apennines. The literary sources indicate that after these conflicts much of the Italian countryside was both lawless, as men strove to take advantage of the breakdown in order, and miserable.

The extension of citizenship to the allies also redrew the political and legal maps of Italy. In place of the former sovereign and autonomous Italian communities, there was a sea of Roman citizen municipia. Municipal constitutions dating from time immemorial over the next decades were replaced by laws and charters passed under the auspices of the comitia in Rome. The varying magistrates of the Italian city-states were largely replaced by a relatively uniform quattorvirate of city magistrates and more rarely with a duovirate. The dating of this municipalisation process is not entirely straightforward: the formation of the quattorvirates likely dates to the Cinnanum tempus; a uniform and generalised lex municipalis came only during the time of Caesar and Augustus.

Enrolment of new citizens
One of the main issues in 88 BC (the consulship of Lucius Cornelius Sulla) was how the newly enfranchised Italian citizens would be enrolled into the Roman tribes. The thirty-five tribes made up the comitia tributa, a Roman popular legislative and electoral assembly. With each tribe getting one vote irrespective of population and with tribal status being hereditary, how the enormous multitude of Italian citizens were tribally organised would sway politics for generations.

The first proposals, emerging during the Social war itself, were merely to expand the number of tribes and to allot the Italians to those new tribes. This solution was also elegantly traditional: Rome's tribes had in the past been adduced to represent citizens living in new territories, though the last time this had been done was in 242 BC. Plans were made to create possibly two or eight new tribes, pursuant to the lex Julia, which would deprive the overwhelming number of new citizens of much of their political influence. Appian further posits this number may have been ten. During Sulla's consulship, one of the tribunes of the plebs, Publius Sulpicius Rufus, challenged this plan. He brought and passed legislation, possibly by force, which would have the new citizens inscribed in the existing thirty-five tribes instead; he could only bring that proposal successfully with the support of Marius, whom he won over with the promise of the Mithridatic command. But his legislation was abrogated after Sulla – at the time continuing the siege at Nola – marched on Rome in response to the Mithridatic reassignment.

After Lucius Cornelius Cinna took control of the city, espousing the cause of Italian suffrage, he settled the matter in favour of distributing the new citizens among the old tribes, which was confirmed during and after Sulla's civil war both by the victor and the senate. This process started only in 70 BC with the election of new censors, who very likely stepped down before the census was complete. This was not helped by the irregular election of censors after the Social war: only two pairs completed their tasks (those of 86 and 70 BC). The process of registering those new citizens, however, took many years – probably delayed by Rome's purposeful inaction – and was only completed during the reign of Augustus.

The new citizens that were enrolled after the Social war also were distributed across the whole of the Italian peninsula. Only a few had the means to travel to Rome and vote in person. Those nearer the city likely had little connection to Rome's oligarchic political system. This new electorate was therefore de facto more concentrated into those who had vested personal interests in the elections. Moreover, because no censuses were held to reclassify citizens on their wealth, those grandfathered into the upper centuriae who had fallen on harder times sold their votes to the highest bidders. The distribution of the tribes across the whole of Italy also empowered magnates close to Rome, whose votes were few and the focus of much political and financial attention.

The impact of these new Italian citizens was felt, for example, in the legislation recalling Cicero from exile in 58 BC. It passed due to the support of the Italian landowners who had been enfranchised by the conflict, using Italian enfranchisement to support Italian political champions.

Destabilisation of the republic
The immediate aftermath of the war proved grounds for continued conflict. Beyond the unrest associated with Sulpicius' tribunate and Sulla's overturning of Sulpicius' laws, the continuing dispute over enfranchisement was one of the factors which motivated men to support Lucius Cornelius Cinna, who posed as a champion for the Italians to gain their support during the bellum Octavianum. Both Cinna and Gnaeus Papirius Carbo, during preparations for civil war against Sulla, stoked fears that Sulla might – if victorious – strip some Italians of their hard-won citizenship rights by abrogating Cinna-era legislation.

Longer-term impacts also were triggered by the war's change in political norms. In the immediate sense, of domestic politics in the period 91–88 BC, nothing at all can be said with certainty. But the war's extensive militarisation of Italy triggered an opening for generals to grab political power:

"[It brought] for the first time in over a hundred years... large-scale military campaigning back to Italian soil. The impact on Roman politics was profound as well as instantaneous. Already in 88, Sulla exploited the presence of standing armies in Italy to seize power and for a period suspended the republican government altogether... [the war] offered unprecedented opportunities for generals to grab power."

The war also politicised the Roman army and broke down civil-military norms. Defections, lax discipline, and mutinies were tolerated as commanders could not afford to lose the support of the men. Conflict with the Italians also blurred the distinction between Romans and foreign enemies: for Andrew Lintott, "Roman armies were only to be used for civil war after their scruples had been drowned in a blood-bath of fighting with their own Italian allies... it may as well be argued that civil war created the self-seeking unprincipled soldier as the converse".

Harriet Flower, in the influential 2010 book Roman republics, further speculates that the conflict may have driven a wedge between the common soldiery and the voters at Rome, reducing their loyalty to the state. Combined, these factors made the republic's victory in the Social war "a Pyrrhic one at best", creating "both Sulla the consul and Sulla's own particular kind of client army that was willing to march on Rome at his bidding, for the first time in Roman history".

Historiography

Views on the Social war have changed over the years. For many years, scholars accepted the Appianic account of demands for Roman citizenship. More recently, however, a "much debated" re-evaluation emerged with the publication of Henrik Mouritsen's Italian Unification in 1998, which read the war not as a struggle for citizenship and political equality, as depicted in imperial accounts, but rather as an attempt by certain Italian allies to throw off the Roman yoke. Archaeological evidence also has continued to show substantial heterogeneity prior to Roman assumption of direct rule over the peninsula. These field surveys have brought up new work in reassessing the extent of Italian regionalism in economic, military, and social terms.

Ancient accounts
Most of the ancient accounts attributed the war to allied demands for citizenship. However, these accounts were written in the aftermath of the war, which extended that citizenship, and largely fail to justify how citizenship became an Italian demand. The core surviving source is Appian; other literary accounts – such as those of Lucius Cornelius Sisenna, Lucullus, Sulla, Diodorus Siculus, and Livy (who wrote more on the Social war than the Second Punic War) – are fragmentary or lost. No Italian perspectives survive, except that which can be gleamed from the few Italian coins.

The earliest accounts of the Social war emerge before the fall of the republic. The first is an excerpt of what is believed to be Posidonius' history of Rome preserved by Diodorus Siculus via Photius. It was written some time between 70 and 65 BC and describes two Italian motives: demands for citizenship which were refused and rebellion against Roman hegemony ("The Italians, who so many times before had fought with distinction on behalf of Rome's hegemonia, were now risking life and limb to secure their own").

The sources also attribute to the allies demands for libertas, a broad term describing legal protections against unjust punishment, the vote, the right to appeal, and the rule of law. Sources voicing demands for libertas include Rhetorica ad Herennium, in which a speech is putatively being given before the quaestio Varia in which the Italians are painted as rebelling against Roman rule. The later poet Ovid also sings of the Paeligni, which Ovid claims had been "compelled to honest arms" by their "love of liberty" (either from Roman hegemony or the burdens of their alliances). An explicit statement to this effect comes also from Strabo, where the Italians rose up seeking liberty, citizenship, and equality with the Romans. Similarly, Eutropius attributes the insurgents as fighting for "equal freedom".

Modern accounts
The first coherent study of the Social war was that of Prosper Mérimée in 1841. The first modern narrative history was that of Adolf Kiene in 1844, which established the narrative separation between northern and southern fronts and cast the consuls of 90 BC as engaging in a personalistic feud with their Italian counterparts. Kiene also was the first to recognise the impact and occurrence of delays in the registration of the new citizens.

Theodor Mommsen was the first to break from the ancient accounts, arguing that the Italian goals shifted during the war from citizenship before the war to independence during it, viewing this as a consequence of the Italian's parallel political institutions established at Corfinium and their christening of a new state called Italia. Other historians also hold this view, including Gaetano De Sanctis (drawing parallels between the Social war-era Italians and 19th century risorgimento) and, most influentially and radically, Henrik Mouritsen.

Mouritsen's account, in the 1998 book Italian Unification, paints the dominant Appianic narrative as being coloured by his second century AD imperialist world view and thereby creating an anachronistic and inaccurate interpretation of first century Italian war goals. He identifies two separate traditions, one for citizenship and one for independence. Mouritsen's account has been extremely influential in recent research, both in terms of a more convincing reconstruction of the war's start, especially in a non-teleological manner, but also in triggering scholarly re-evaluation of Romanisation in Italy and Italian war goals more generally. It has not, however, won universal acceptance. Other scholars have also connected the burdens of allied service in the Roman army with resentment against segregation and mistreatment.

Modern sources

title: Social War (91–87 BC)


text:
Arthur Adamov

Arthur Adamov (23 August 1908 – 15 March 1970) was a playwright, one of the foremost exponents of the Theatre of the Absurd.

Early life
Adamov (originally Adamian) was born in Kislovodsk in the Terek Oblast of the Russian Empire to a wealthy Armenian family. :92 At the outbreak of the First World War, the family was at risk of being interned as "enemy citizens", and only "through the special intervention of the King of Wurttemberg" were they able to escape to Geneva, Switzerland. :93 Adamov was educated in Switzerland and Germany, :93 with French as his primary language. In 1924, when he was sixteen years old, he moved to Paris, France. :93 There he met artists associated with the Surrealist Movement and edited the surrealist journal Discontinuité. :93

Postwar career
He began to write plays at the end of World War II. :98 La Parodie (1947) was his first play, which Martin Esslin has identified as "an attempt to come to terms with neurosis, to make psychological states visible in concrete terms". :98 His work, influenced by Bertolt Brechtand August Strindberg, :98 is often dream-like and later works in particular have a political element. The title character of one of his best known works, Le Professeur Taranne (1953), is accused of various things (public nudity, littering, plagiarism), all of which he strenuously denies, only to have his denials turned against him into more evidence of misdemeanours. This particular play was directly influenced by a dream Adamov had.

Lesser known to the public is his prose work with short stories such as "Fin Août" (in Je... Ils..., 1969). Their themes revolve around topics including masochism, which the author regarded as "immunisation against death". Adamov translated a number of works by German authors (Rilke, Büchner) and Russian classics (Gogol, Chekhov) into French.

The Algerian war radicalised his political views and in the 1960s he became a Communist.

During his later years, he began to drink and use drugs.

Adamov's death in 1970 was due to an overdose of barbiturates.

Selected works

 * L'Aveu (The Confession, 1946)
 * La Parodie (The Parody, 1950)
 * L'Invasion (The Invasion, 1950)
 * La Grande et la Petite Manoeuvre (The Grand and Small Manoeuvre, 1950)
 * Le Sens de la Marche (The Way to Go, 1953)
 * Tous contre tous (All against all, 1953)
 * Le Professeur Taranne (Professor Taranne, 1953)
 * Le Ping-Pong (Ping Pong, 1955)
 * Paolo Paoli (1957)
 * Le Printemps '71 (Spring '71, 1960)
 * La Politique des Restes (The Politics of Rubbish'', 1963)
 * Ici et Maintenant (Here and Now, 1964)
 * Sainte Europe (Holy Europe, 1966)
 * M. le Modéré (Mr. Moderate, 1968)
 * Off Limits (1969)
 * Si l'été revenait (If Summer Came Again, 1970)

license: Creative Commons - Attribution Share-Alike - https://creativecommons.org/licenses/by-sa/4.0/

title: Arthur Adamov


text:
Pyrolysis

Pyrolysis is the process of thermal decomposition of materials at elevated temperatures, often in an inert atmosphere.

Etymology
The word pyrolysis is coined from the Greek-derived elements pyro- (from Ancient Greek πῦρ : pûr - "fire, heat, fever") and lysis (λύσις : lúsis - "separation, loosening").

Applications
Pyrolysis is most commonly used in the treatment of organic materials. It is one of the processes involved in charring wood. In general, pyrolysis of organic substances produces volatile products and leaves char, a carbon-rich solid residue. Extreme pyrolysis, which leaves mostly carbon as the residue, is called carbonization. Pyrolysis is considered the first step in the processes of gasification or combustion.

The process is used heavily in the chemical industry, for example, to produce ethylene, many forms of carbon, and other chemicals from petroleum, coal, and even wood, or to produce coke from coal. It is used also in the conversion of natural gas (primarily methane) into hydrogen gas and solid carbon char, recently introduced on an industrial scale. Aspirational applications of pyrolysis would convert biomass into syngas and biochar, waste plastics back into usable oil, or waste into safely disposable substances.

Terminology
Pyrolysis is one of the various types of chemical degradation processes that occur at higher temperatures (above the boiling point of water or other solvents). It differs from other processes like combustion and hydrolysis in that it usually does not involve the addition of other reagents such as oxygen (O2, in combustion) or water (in hydrolysis). Pyrolysis produces solids (char), condensable liquids, (light and heavy oils and tar), and non-condensable gasses.

Pyrolysis is different from gasification. In the chemical process industry, pyrolysis refers to a partial thermal degradation of carbonaceous materials that takes place in an inert (oxygen free) atmosphere and produces both gases, liquids and solids. The pyrolysis can be extended to full gasification that produces mainly gaseous output, often with the addition of e.g. water steam to gasify residual carbonic solids, see Steam reforming.

Types
Specific types of pyrolysis include:
 * Carbonization, the complete pyrolysis of organic matter, which usually leaves a solid residue that consists mostly of elemental carbon.
 * Methane pyrolysis, the direct conversion of methane to hydrogen fuel and separable solid carbon, sometimes using molten metal catalysts.
 * Hydrous pyrolysis, in the presence of superheated water or steam, producing hydrogen and substantial atmospheric carbon dioxide.
 * Dry distillation, as in the original production of sulfuric acid from sulfates.
 * Destructive distillation, as in the manufacture of charcoal, coke and activated carbon.
 * Charcoal burning, the production of charcoal.
 * Tar production by destructive distillation of wood in tar kilns.
 * Caramelization of sugars.
 * High-temperature cooking processes such as roasting, frying, toasting, and grilling.
 * Cracking of heavier hydrocarbons into lighter ones, as in oil refining.
 * Thermal depolymerization, which breaks down plastics and other polymers into monomers and oligomers.
 * Ceramization involving the formation of polymer derived ceramics from preceramic polymers under an inert atmosphere.
 * Catagenesis, the natural conversion of buried organic matter to fossil fuels.
 * Flash vacuum pyrolysis, used in organic synthesis.

Other pyrolysis types come from a different classification that focuses on the pyrolysis operating conditions and heating system used, which have an impact on the yield of the pyrolysis products.

History
Pyrolysis has been used for turning wood into charcoal since ancient times. The ancient Egyptians used the liquid fraction obtained from the pyrolysis of cedar wood, in their embalming process.

The dry distillation of wood remained the major source of methanol into the early 20th century. Pyrolysis was instrumental in the discovery of many chemical substances, such as phosphorus from ammonium sodium hydrogen phosphate NH4NaHPO4 in concentrated urine, oxygen from mercuric oxide, and various nitrates.

General processes and mechanisms

Pyrolysis generally consists in heating the material above its decomposition temperature, breaking chemical bonds in its molecules. The fragments usually become smaller molecules, but may combine to produce residues with larger molecular mass, even amorphous covalent solids.

In many settings, some amounts of oxygen, water, or other substances may be present, so that combustion, hydrolysis, or other chemical processes may occur besides pyrolysis proper. Sometimes those chemicals are added intentionally, as in the burning of firewood, in the traditional manufacture of charcoal, and in the steam cracking of crude oil.

Conversely, the starting material may be heated in a vacuum or in an inert atmosphere to avoid chemical side reactions (such as combustion or hydrolysis). Pyrolysis in a vacuum also lowers the boiling point of the byproducts, improving their recovery.

When organic matter is heated at increasing temperatures in open containers, the following processes generally occur, in successive or overlapping stages:

 * Below about 100 °C, volatiles, including some water, evaporate. Heat-sensitive substances, such as vitamin C and proteins, may partially change or decompose already at this stage.
 * At about 100 °C or slightly higher, any remaining water that is merely absorbed in the material is driven off. This process consumes a lot of energy, so the temperature may stop rising until all water has evaporated. Water trapped in crystal structure of hydrates may come off at somewhat higher temperatures.
 * Some solid substances, like fats, waxes, and sugars, may melt and separate.
 * Between 100 and 500 °C, many common organic molecules break down. Most sugars start decomposing at 160–180 °C. Cellulose, a major component of wood, paper, and cotton fabrics, decomposes at about 350 °C. Lignin, another major wood component, starts decomposing at about 350 °C, but continues releasing volatile products up to 500 °C. The decomposition products usually include water, carbon monoxide CO and/or carbon dioxide CO2, as well as a large number of organic compounds. Gases and volatile products leave the sample, and some of them may condense again as smoke. Generally, this process also absorbs energy. Some volatiles may ignite and burn, creating a visible flame. The non-volatile residues typically become richer in carbon and form large disordered molecules, with colors ranging between brown and black. At this point the matter is said to have been "charred" or "carbonized".
 * At 200–300 °C, if oxygen has not been excluded, the carbonaceous residue may start to burn, in a highly exothermic reaction, often with no or little visible flame. Once carbon combustion starts, the temperature rises spontaneously, turning the residue into a glowing ember and releasing carbon dioxide and/or monoxide. At this stage, some of the nitrogen still remaining in the residue may be oxidized into nitrogen oxides like NO2 and N2O3. Sulfur and other elements like chlorine and arsenic may be oxidized and volatilized at this stage.
 * Once combustion of the carbonaceous residue is complete, a powdery or solid mineral residue (ash) is often left behind, consisting of inorganic oxidized materials of high melting point. Some of the ash may have left during combustion, entrained by the gases as fly ash or particulate emissions. Metals present in the original matter usually remain in the ash as oxides or carbonates, such as potash. Phosphorus, from materials such as bone, phospholipids, and nucleic acids, usually remains as phosphates.

Safety challenges
Because pyrolysis takes place at high temperatures which exceed the autoignition temperature of the produced gases, an explosion risk exists if oxygen is present. To control the temperature of pyrolysis systems careful temperature control is needed and can be accomplished with an open source pyrolysis controller. Pyrolysis also produces various toxic gases, mainly carbon monoxide. The greatest risk of fire, explosion and release of toxic gases comes when the system is starting up and shutting down, operating intermittently, or during operational upsets.

Inert gas purging is essential to manage inherent explosion risks. The procedure is not trivial and failure to keep oxygen out has led to accidents.

Cooking
Pyrolysis has many applications in food preparation. Caramelization is the pyrolysis of sugars in food (often after the sugars have been produced by the breakdown of polysaccharides). The food goes brown and changes flavor. The distinctive flavors are used in many dishes; for instance, caramelized onion is used in French onion soup. The temperatures needed for caramelization lie above the boiling point of water. Frying oil can easily rise above the boiling point. Putting a lid on the frying pan keeps the water in, and some of it re-condenses, keeping the temperature too cool to brown for longer time.

Pyrolysis of food can also be undesirable, as in the charring of burnt food (at temperatures too low for the oxidative combustion of carbon to produce flames and burn the food to ash).

Coke, carbon, charcoals, and chars

Carbon and carbon-rich materials have desirable properties but are nonvolatile, even at high temperatures. Consequently, pyrolysis is used to produce many kinds of carbon; these can be used for fuel, as reagents in steelmaking (coke), and as structural materials.

Charcoal is a less smoky fuel than pyrolyzed wood. Some cities ban, or used to ban, wood fires; when residents only use charcoal (and similarly treated rock coal, called coke) air pollution is significantly reduced. In cities where people do not generally cook or heat with fires, this is not needed. In the mid-20th century, "smokeless" legislation in Europe required cleaner-burning techniques, such as coke fuel and smoke-burning incinerators as an effective measure to reduce air pollution

The coke-making or "coking" process consists of heating the material in "coking ovens" to very high temperatures (up to 900 C) so that the molecules are broken down into lighter volatile substances, which leave the vessel, and a porous but hard residue that is mostly carbon and inorganic ash. The amount of volatiles varies with the source material, but is typically 25–30% of it by weight. High temperature pyrolysis is used on an industrial scale to convert coal into coke. This is useful in metallurgy, where the higher temperatures are necessary for many processes, such as steelmaking. Volatile by-products of this process are also often useful, including benzene and pyridine. Coke can also be produced from the solid residue left from petroleum refining.

The original vascular structure of the wood and the pores created by escaping gases combine to produce a light and porous material. By starting with a dense wood-like material, such as nutshells or peach stones, one obtains a form of charcoal with particularly fine pores (and hence a much larger pore surface area), called activated carbon, which is used as an adsorbent for a wide range of chemical substances.

Biochar is the residue of incomplete organic pyrolysis, e.g., from cooking fires. It is a key component of the terra preta soils associated with ancient indigenous communities of the Amazon basin. Terra preta is much sought by local farmers for its superior fertility and capacity to promote and retain an enhanced suite of beneficial microbiota, compared to the typical red soil of the region. Efforts are underway to recreate these soils through biochar, the solid residue of pyrolysis of various materials, mostly organic waste. Carbon fibers are filaments of carbon that can be used to make very strong yarns and textiles. Carbon fiber items are often produced by spinning and weaving the desired item from fibers of a suitable polymer, and then pyrolyzing the material at a high temperature (from 1500 - 3000 °C). The first carbon fibers were made from rayon, but polyacrylonitrile has become the most common starting material. For their first workable electric lamps, Joseph Wilson Swan and Thomas Edison used carbon filaments made by pyrolysis of cotton yarns and bamboo splinters, respectively.

Pyrolysis is the reaction used to coat a preformed substrate with a layer of pyrolytic carbon. This is typically done in a fluidized bed reactor heated to 1000 - 2000 °C. Pyrolytic carbon coatings are used in many applications, including artificial heart valves.

Liquid and gaseous biofuels
Pyrolysis is the basis of several methods for producing fuel from biomass, i.e. lignocellulosic biomass. Crops studied as biomass feedstock for pyrolysis include native North American prairie grasses such as switchgrass and bred versions of other grasses such as Miscantheus giganteus. Other sources of organic matter as feedstock for pyrolysis include greenwaste, sawdust, waste wood, leaves, vegetables, nut shells, straw, cotton trash, rice hulls, and orange peels. Animal waste including poultry litter, dairy manure, and potentially other manures are also under evaluation. Some industrial byproducts are also suitable feedstock including paper sludge, distillers grain, and sewage sludge.

In the biomass components, the pyrolysis of hemicellulose happens between 210 and 310 °C. The pyrolysis of cellulose starts from 300 to 315 °C and ends at 360–380 °C, with a peak at 342–354 °C. Lignin starts to decompose at about 200 °C and continues until 1000 °C.

Synthetic diesel fuel by pyrolysis of organic materials is not yet economically competitive. Higher efficiency is sometimes achieved by flash pyrolysis, in which finely divided feedstock is quickly heated to between 350 and 500 °C for less than two seconds.

Syngas is usually produced by pyrolysis.

The low quality of oils produced through pyrolysis can be improved by physical and chemical processes, which might drive up production costs, but may make sense economically as circumstances change.

There is also the possibility of integrating with other processes such as mechanical biological treatment and anaerobic digestion. Fast pyrolysis is also investigated for biomass conversion. Fuel bio-oil can also be produced by hydrous pyrolysis.

Methane pyrolysis for hydrogen
Methane pyrolysis is an industrial process for "turquoise" hydrogen production from methane by removing solid carbon from natural gas. This one-step process produces hydrogen in high volume at low cost (less than steam reforming with carbon sequestration). No greenhouse gas is released. No deep well injection of carbon dioxide is needed. Only water is released when hydrogen is used as the fuel for fuel-cell electric heavy truck transportation, gas turbine electric power generation, and hydrogen for industrial processes including producing ammonia fertilizer and cement. Methane pyrolysis is the process operating around 1065 °C for producing hydrogen from natural gas that allows removal of carbon easily (solid carbon is a byproduct of the process). The industrial quality solid carbon can then be sold or landfilled and is not released into the atmosphere, avoiding emission of greenhouse gas (GHG) or ground water pollution from a landfill. In 2015, a company called Monolith Materials built a pilot plant in Redwood City, CA to study scaling Methane Pyrolysis using renewable power in the process. A successful pilot project then led to a larger commercial-scale demonstration plant in Hallam, Nebraska in 2016. As of 2020, this plant is operational and can produce around 14 metric tons of hydrogen per day. In 2021, the US Department of Energy backed Monolith Materials' plans for major expansion with a $1B loan guarantee. The funding will help produce a plant capable of generating 164 metric tons of hydrogen per day by 2024. Pilots with gas utilities and biogas plants are underway with companies like Modern Hydrogen. Volume production is also being evaluated in the BASF "methane pyrolysis at scale" pilot plant, the chemical engineering team at University of California - Santa Barbara and in such research laboratories as Karlsruhe Liquid-metal Laboratory (KALLA). Power for process heat consumed is only one-seventh of the power consumed in the water electrolysis method for producing hydrogen.

The Australian company Hazer Group was founded in 2010 to commercialise technology originally developed at the University of Western Australia. The company was listed on the ASX in December 2015. It is completing a commercial demonstration project to produce renewable hydrogen and graphite from wastewater and iron ore as a process catalyst use technology created by the University of Western Australia (UWA). The Commercial Demonstration Plant project is an Australian first, and expected to produce around 100 tonnes of fuel-grade hydrogen and 380 tonnes of graphite each year starting in 2023. It was scheduled to commence in 2022. "10 December 2021: Hazer Group (ASX: HZR) regret to advise that there has been a delay to the completion of the fabrication of the reactor for the Hazer Commercial Demonstration Project (CDP). This is expected to delay the planned commissioning of the Hazer CDP, with commissioning now expected to occur after our current target date of 1Q 2022." The Hazer Group has collaboration agreements with Engie for a facility in France in May 2023, A Memorandum of Understanding with Chubu Electric & Chiyoda in Japan April 2023 and an agreement with Suncor Energy and FortisBC to develop 2,500 tonnes per Annum Burrard-Hazer Hydrogen Production Plant in Canada April 2022

The American company C-Zero's technology converts natural gas into hydrogen and solid carbon. The hydrogen provides clean, low-cost energy on demand, while the carbon can be permanently sequestered. C-Zero announced in June 2022 that it closed a $34 million financing round led by SK Gas, a subsidiary of South Korea's second-largest conglomerate, the SK Group. SK Gas was joined by two other new investors, Engie New Ventures and Trafigura, one of the world's largest physical commodities trading companies, in addition to participation from existing investors including Breakthrough Energy Ventures, Eni Next, Mitsubishi Heavy Industries, and AP Ventures. Funding was for C-Zero's first pilot plant, which was expected to be online in Q1 2023. The plant may be capable of producing up to 400 kg of hydrogen per day from natural gas with no CO2 emissions. One of the world's largest chemical companies, BASF, has been researching hydrogen pyrolysis for more than 10 years.

Ethylene
Pyrolysis is used to produce ethylene, the chemical compound produced on the largest scale industrially (>110 million tons/year in 2005). In this process, hydrocarbons from petroleum are heated to around 600 C in the presence of steam; this is called steam cracking. The resulting ethylene is used to make antifreeze (ethylene glycol), PVC (via vinyl chloride), and many other polymers, such as polyethylene and polystyrene.

Semiconductors
The process of metalorganic vapour-phase epitaxy (MOCVD) entails pyrolysis of volatile organometallic compounds to give semiconductors, hard coatings, and other applicable materials. The reactions entail thermal degradation of precursors, with deposition of the inorganic component and release of the hydrocarbons as gaseous waste. Since it is an atom-by-atom deposition, these atoms organize themselves into crystals to form the bulk semiconductor. Raw polycrystalline silicon is produced by the chemical vapor deposition of silane gases:
 * SiH4 →  Si  +  2 H2.

Gallium arsenide, another semiconductor, forms upon co-pyrolysis of trimethylgallium and arsine.

Waste management
Pyrolysis can also be used to treat municipal solid waste and plastic waste. The main advantage is the reduction in volume of the waste. In principle, pyrolysis will regenerate the monomers (precursors) to the polymers that are treated, but in practice the process is neither a clean nor an economically competitive source of monomers.

In tire waste management, tire pyrolysis is a well-developed technology. Other products from car tire pyrolysis include steel wires, carbon black and bitumen. The area faces legislative, economic, and marketing obstacles. Oil derived from tire rubber pyrolysis has a high sulfur content, which gives it high potential as a pollutant; consequently it should be desulfurized.

Alkaline pyrolysis of sewage sludge at low temperature of 500 °C can enhance H2 production with in-situ carbon capture. The use of NaOH (sodium hydroxide) has the potential to produce H2-rich gas that can be used for fuels cells directly.

In early November 2021, the U.S. State of Georgia announced a joint effort with Igneo Technologies to build an $85 million large electronics recycling plant in the Port of Savannah. The project will focus on lower-value, plastics-heavy devices in the waste stream using multiple shredders and furnaces using pyrolysis technology.

One-stepwise pyrolysis and Two-stepwise pyrolysis for Tobacco Waste
Pyrolysis has also been used for trying to mitigate tobacco waste. One method was done where tobacco waste was separated into two categories TLW (Tobacco Leaf Waste) and TSW (Tobacco Stick Waste). TLW was determined to be any waste from cigarettes and TSW was determined to be any waste from electronic cigarettes. Both TLW and TSW were dried at 80 °C for 24 hours and stored in a desiccator. Samples were grounded so that the contents were uniform. Tobacco Waste (TW) also contains inorganic (metal) contents, which was determined using an inductively coupled plasma-optical spectrometer. Thermo-gravimetric analysis was used to thermally degrade four samples (TLW, TSW, glycerol, and guar gum) and monitored under specific dynamic temperature conditions. About one gram of both TLW and TSW were used in the pyrolysis tests. During these analysis tests, CO2 and N2 were used as atmospheres inside of a tubular reactor that was built using quartz tubing. For both CO2 and N2 atmospheres the flow rate was 100 mL min−1. External heating was created via a tubular furnace. The pyrogenic products were classified into three phases. The first phase was biochar, a solid residue produced by the reactor at 650 °C. The second phase liquid hydrocarbons were collected by a cold solvent trap and sorted by using chromatography. The third and final phase was analyzed using an online micro GC unit and those pyrolysates were gases.

Two different types of experiments were conducted: one-stepwise pyrolysis and two-stepwise pyrolysis. One-stepwise pyrolysis consisted of a constant heating rate (10 °C min−1) from 30 to 720 °C. In the second step of the two-stepwise pyrolysis test the pyrolysates from the one-stepwise pyrolysis were pyrolyzed in the second heating zone which was controlled isothermally at 650 °C. The two-stepwise pyrolysis was used to focus primarily on how well CO2 affects carbon redistribution when adding heat through the second heating zone.

First noted was the thermolytic behaviors of TLW and TSW in both the CO2 and N2 environments. For both TLW and TSW the thermolytic behaviors were identical at less than or equal to 660 °C in the CO2 and N2 environments. The differences between the environments start to occur when temperatures increase above 660 °C and the residual mass percentages significantly decrease in the CO2 environment compared to that in the N2 environment. This observation is likely due to the Boudouard reaction, where we see spontaneous gasification happening when temperatures exceed 710 °C. Although these observations were seen at temperatures lower than 710 °C it is most likely due to the catalytic capabilities of inorganics in TLW. It was further investigated by doing ICP-OES measurements and found that a fifth of the residual mass percentage was Ca species. CaCO3 is used in cigarette papers and filter material, leading to the explanation that degradation of CaCO3 causes pure CO2 reacting with CaO in a dynamic equilibrium state. This being the reason for seeing mass decay between 660 °C and 710 °C. Differences in differential thermogram (DTG) peaks for TLW were compared to TSW. TLW had four distinctive peaks at 87, 195, 265, and 306 °C whereas TSW had two major drop offs at 200 and 306 °C with one spike in between. The four peaks indicated that TLW contains more diverse types of additives than TSW. The residual mass percentage between TLW and TSW was further compared, where the residual mass in TSW was less than that of TLW for both CO2 and N2 environments concluding that TSW has higher quantities of additives than TLW.

The one-stepwise pyrolysis experiment showed different results for the CO2 and N2 environments. During this process the evolution of 5 different notable gases were observed. Hydrogen, Methane, Ethane, Carbon Dioxide, and Ethylene all are produced when the thermolytic rate of TLW began to be retarded at greater than or equal to 500 °C. Thermolytic rate begins at the same temperatures for both the CO2 and N2 environment but there is higher concentration of the production of Hydrogen, Ethane, Ethylene, and Methane in the N2 environment than that in the CO2 environment. The concentration of CO in the CO2 environment is significantly greater as temperatures increase past 600 °C and this is due to CO2 being liberated from CaCO3 in TLW. This significant increase in CO concentration is why there is lower concentrations of other gases produced in the CO2 environment due to a dilution effect. Since pyrolysis is the re-distribution of carbons in carbon substrates into three pyrogenic products. The CO2 environment is going to be more effective because the CO2 reduction into CO allows for the oxidation of pyrolysates to form CO. In conclusion the CO2 environment allows a higher yield of gases than oil and biochar. When the same process is done for TSW the trends are almost identical therefore the same explanations can be applied to the pyrolysis of TSW.

Harmful chemicals were reduced in the CO2 environment due to CO formation causing tar to be reduced. One-stepwise pyrolysis was not that effective on activating CO2 on carbon rearrangement due to the high quantities of liquid pyrolysates (tar). Two-stepwise pyrolysis for the CO2 environment allowed for greater concentrations of gases due to the second heating zone. The second heating zone was at a consistent temperature of 650 °C isothermally. More reactions between CO2 and gaseous pyrolysates with longer residence time meant that CO2 could further convert pyrolysates into CO. The results showed that the two-stepwise pyrolysis was an effective way to decrease tar content and increase gas concentration by about 10 wt.% for both TLW (64.20 wt.%) and TSW (73.71%).

Thermal cleaning
Pyrolysis is also used for thermal cleaning, an industrial application to remove organic substances such as polymers, plastics and coatings from parts, products or production components like extruder screws, spinnerets and static mixers. During the thermal cleaning process, at temperatures from 310 to 540 C, organic material is converted by pyrolysis and oxidation into volatile organic compounds, hydrocarbons and carbonized gas. Inorganic elements remain.

Several types of thermal cleaning systems use pyrolysis:
 * Molten Salt Baths belong to the oldest thermal cleaning systems; cleaning with a molten salt bath is very fast but implies the risk of dangerous splatters, or other potential hazards connected with the use of salt baths, like explosions or highly toxic hydrogen cyanide gas.
 * Fluidized Bed Systems use sand or aluminium oxide as heating medium; these systems also clean very fast but the medium does not melt or boil, nor emit any vapors or odors; the cleaning process takes one to two hours.
 * Vacuum Ovens use pyrolysis in a vacuum avoiding uncontrolled combustion inside the cleaning chamber; the cleaning process takes 8 to 30 hours.
 * Burn-Off Ovens, also known as Heat-Cleaning Ovens, are gas-fired and used in the painting, coatings, electric motors and plastics industries for removing organics from heavy and large metal parts.

Fine chemical synthesis
Pyrolysis is used in the production of chemical compounds, mainly, but not only, in the research laboratory.

The area of boron-hydride clusters started with the study of the pyrolysis of diborane (B2H6) at ca. 200 °C. Products include the clusters pentaborane and decaborane. These pyrolyses involve not only cracking (to give H2), but also recondensation.

The synthesis of nanoparticles, zirconia and oxides utilizing an ultrasonic nozzle in a process called ultrasonic spray pyrolysis (USP).

Other uses and occurrences

 * Pyrolysis is used to turn organic materials into carbon for the purpose of carbon-14 dating.
 * Pyrolysis liquids from slow pyrolysis of bark and hemp have been tested for their antifungal activity against wood decaying fungi, showing potential to substitute the current wood preservatives while further tests are still required. However, their ecotoxicity is very variable and while some are less toxic than current wood preservatives, other pyrolysis liquids have shown high ecotoxicity, what may cause detrimental effects in the environment.
 * Pyrolysis of tobacco, paper, and additives, in cigarettes and other products, generates many volatile products (including nicotine, carbon monoxide, and tar) that are responsible for the aroma and negative health effects of smoking. Similar considerations apply to the smoking of marijuana and the burning of incense products and mosquito coils.
 * Pyrolysis occurs during the incineration of trash, potentially generating volatiles that are toxic or contribute to air pollution if not completely burned.
 * Laboratory or industrial equipment sometimes gets fouled by carbonaceous residues that result from coking, the pyrolysis of organic products that come into contact with hot surfaces.

PAHs generation
Polycyclic aromatic hydrocarbons (PAHs) can be generated from the pyrolysis of different solid waste fractions, such as hemicellulose, cellulose, lignin, pectin, starch, polyethylene (PE), polystyrene (PS), polyvinyl chloride (PVC), and polyethylene terephthalate (PET). PS, PVC, and lignin generate significant amount of PAHs. Naphthalene is the most abundant PAH among all the polycyclic aromatic hydrocarbons.

When the temperature is increased from 500 to 900 °C, most PAHs increase. With increasing temperature, the percentage of light PAHs decreases and the percentage of heavy PAHs increases.

Thermogravimetric analysis
Thermogravimetric analysis (TGA) is one of the most common techniques to investigate pyrolysis with no limitations of heat and mass transfer. The results can be used to determine mass loss kinetics. Activation energies can be calculated using the Kissinger method or peak analysis-least square method (PA-LSM).

TGA can couple with Fourier-transform infrared spectroscopy (FTIR) and mass spectrometry. As the temperature increases, the volatiles generated from pyrolysis can be measured.

Macro-TGA
In TGA, the sample is loaded first before the increase of temperature, and the heating rate is low (less than 100 °C min−1). Macro-TGA can use gram-scale samples, which can be used to investigate the pyrolysis with mass and heat transfer effects.

Pyrolysis–gas chromatography–mass spectrometry
Pyrolysis mass spectrometry (Py-GC-MS) is an important laboratory procedure to determine the structure of compounds.

Machine learning
In recent years, machine learning has attracted significant research interest in predicting yields, optimizing parameters, and monitoring pyrolytic processes.

title: Pyrolysis


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Philly Joe Jones

Joseph Rudolph "Philly Joe" Jones (July 15, 1923 – August 30, 1985) was an American jazz drummer.

Early career
As a child, Jones appeared as a featured tap dancer on The Kiddie Show on the Philadelphia radio station WIP. He was in the US Army during World War II.

In 1947 he became the house drummer at Café Society in New York City, where he played with the leading bebop players of the day, including Tadd Dameron. From 1955 to 1958, Jones toured and recorded with Miles Davis Quintet — a band that became known as "The Quintet" (along with Red Garland on piano, John Coltrane on sax, and Paul Chambers on bass). Davis acknowledged that Jones was his favorite drummer, and stated in his autobiography that he would always listen for Jones in other drummers.

From 1958, Jones worked as a leader, but continued to work as a sideman with other musicians, including Bill Evans and Hank Mobley. Evans, like Davis, also openly stated that Jones was his all-time favorite drummer.

Europe
Between late 1967 and 1972 Jones lived in London and Paris, performing and recording with musicians including Archie Shepp, Mal Waldron and Hank Mobley. For two years (1967–69) Jones taught at a specially organized school in Hampstead, London, but was prevented from otherwise working in the UK by the Musicians' Union. His 1968 album Mo' Joe (also released as Trailways Express) was recorded in London with local musicians (including Peter King, Harold McNair, Chris Pyne, Kenny Wheeler and others).

Later years
Jones toured with Bill Evans in 1976 and 1978, recorded for Galaxy in 1977–79, and worked with Red Garland. From 1981, Jones helped to found the group Dameronia, dedicated to the music of the composer Tadd Dameron, and led it until his death from a heart attack in 1985.

As sideman
With Chet Baker
 * Chet Baker in New York (Riverside, 1959) – rec. 1958
 * Chet Baker Introduces Johnny Pace with Johnny Pace (Riverside, 1959) – rec. 1958

With Sonny Clark
 * Cool Struttin' (Blue Note, 1958)
 * Sonny Clark Trio (Blue Note, 1958) – rec. 1957

With Miles Davis
 * The Musings of Miles (Prestige, 1955)
 * Miles: The New Miles Davis Quintet (Prestige, 1956)
 * Cookin' with the Miles Davis Quintet (Prestige, 1956)
 * Relaxin' with the Miles Davis Quintet (Prestige, 1956)
 * Workin' with the Miles Davis Quintet (Prestige, 1956)
 * Steamin' with the Miles Davis Quintet (Prestige, 1956)
 * 'Round About Midnight (Columbia, 1957)
 * Porgy and Bess (Columbia, 1958)
 * Milestones (Columbia, 1958)
 * Someday My Prince Will Come (Columbia, 1961)

With Kenny Drew
 * Kenny Drew Trio (Riverside, 1956)
 * Pal Joey (Riverside, 1958) – rec. 1957

With Bill Evans
 * 1958: Everybody Digs Bill Evans (Riverside, 1959)
 * 1959: On Green Dolphin Street (Riverside, 1977)
 * 1962: Interplay (Riverside, 1963)
 * 1967: California Here I Come (Verve, 1982)
 * 1976: Quintessence (Fantasy, 1977)

With Art Farmer
 * Art Farmer Quintet featuring Gigi Gryce (Prestige, 1955)
 * Brass Shout (United Artists, 1959)

With Red Garland
 * Red's Good Groove (Jazzland, 1962)
 * Keystones! (Xanadu, 1977)
 * Crossings (Galaxy, 1978)

With Benny Golson
 * The Other Side of Benny Golson (Riverside, 1958)
 * Benny Golson and the Philadelphians (United Artists, 1958)

With Dexter Gordon
 * Dexter Calling... (Blue Note, 1961)
 * Landslide (Blue Note, 1980) – rec. 1961-1962

With Ernie Henry
 * Seven Standards and a Blues (Riverside, 1957)
 * Last Chorus (Riverside, 1956–1957)

With Elmo Hope
 * The Elmo Hope Trio (Blue Note, 1953)
 * Here's Hope! (Celebrity, 1961)
 * High Hope! (Beacon, 1961)
 * Homecoming! (Riverside, 1961)
 * Sounds from Rikers Island (Audio Fidelity, 1963)
 * The Final Sessions (Evidence, 1996) – rec. 1966

With Freddie Hubbard
 * Goin' Up (Blue Note, 1960)
 * Hub Cap (Blue Note, 1961)
 * Here to Stay (Blue Note, 1962)

With Bobby Hutcherson
 * Four Seasons (Timeless, 1985) – rec. 1983
 * Good Bait (Landmark, 1985) – rec. 1984

With Duke Jordan
 * Duke's Artistry (SteepleChase, 1978)
 * The Great Session (SteepleChase, 1981) – rec. 1978

With Abbey Lincoln
 * It's Magic (Riverside, 1958)
 * Abbey Is Blue (Riverside, 1959)

With Herbie Mann
 * Salute to the Flute (Epic, 1957)
 * Herbie Mann's African Suite (United Artists, 1959)

With Howard McGhee
 * The Return of Howard McGhee (Bethlehem, 1956) – rec. 1955. reissued as That Bop Thing (Bethlehem, 1978)

With Blue Mitchell
 * Big 6 (Riverside, 1958)
 * Smooth as the Wind (Riverside, 1961) – rec. 1960-1961

With Hank Mobley
 * 1957: Hank (Blue Note, 1957)
 * 1957: Poppin' (Blue Note, 1980)
 * 1961: Workout (Blue Note, 1962)
 * 1961: Another Workout (Blue Note, 1985)
 * 1963: No Room for Squares (Blue Note, 1964)

With Phineas Newborn Jr.
 * Phineas' Rainbow (RCA Victor, 1956)
 * A World of Piano! (Contemporary, 1961)

With Sonny Rollins
 * Tenor Madness (Prestige, 1956)
 * Newk's Time (Blue Note, 1957)

With Archie Shepp
 * Blasé (BYG Actuel, 1969)
 * Archie Shepp & Philly Joe Jones (America, 1969)

With Clark Terry
 * Serenade to a Bus Seat (Riverside, 1957)
 * In Orbit (Riverside, 1958)

With others
 * Chris Anderson, Inverted Image (Jazzland, 1961)
 * Evans Bradshaw, Look Out for Evans Bradshaw! (Riverside, 1958)
 * Clifford Brown, Memorial Album (Blue Note, 1953)
 * Kenny Burrell, Ellington Is Forever Volume Two (Fantasy, 1975)
 * Joe Castro, Mood Jazz (Atlantic, 1957)
 * Serge Chaloff, Blue Serge (Capitol, 1956)
 * Paul Chambers, Go (Vee-Jay, 1959)
 * John Coltrane, Blue Train (Blue Note, 1958)
 * Bennie Green, Bennie Green with Art Farmer with Art Farmer (Prestige, 1956)
 * Johnny Griffin, Way Out! (Riverside, 1959)
 * Milt Jackson and Wes Montgomery, Bags Meets Wes! (Riverside, 1962)
 * Clifford Jordan, The Rotterdam Session (Audio Daddio, 1985)
 * Warne Marsh, Warne Marsh (Atlantic, 1958)
 * Yoshiaki Miyanoue, Song for Wes (King Records, 1979)
 * J. R. Monterose, J. R. Monterose (Blue Note, 1956)
 * Art Pepper, Art Pepper Meets the Rhythm Section (Contemporary, 1957)
 * Bud Powell, Time Waits (Blue Note, 1958)
 * Jimmy Smith, Softly as a Summer Breeze (Blue Note, 1958)
 * Sonny Stitt, Sonny Stitt & the Top Brass (Atlantic, 1962)
 * The Manhattan Transfer, Vocalese (Atlantic, 1985)
 * Ben Webster, Soulmates with Joe Zawinul (Riverside, 1963)
 * Jack Wilson, The Two Sides of Jack Wilson (Atlantic, 1964)
 * Phil Woods, Pairing Off (Prestige, 1956)

title: Philly Joe Jones


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User talk:Electric blood

Welcome. Please review our policy of neutral point of view. Thanks -- sannse 16:52 6 Jul 2003 (UTC)

title: User talk:Electric blood


text:
User:Hbruhn

A mathematician is a machine for turning coffee into theorems - Paul Erdös

title: User:Hbruhn