858. The formation of aromatic hydrocarbons at high temperatures. Part IX. The pyrolysis of toluene, ethylbenzene, propylbenzene, and butylbenzene

Abstract

Pyrolyscs of toluene, ethylbenzene, propylbenzene, and b u tylbeuzene have given the compounds listed in thc Table . The yields of higher p l ycyclic hydrocarbons varied with the nature of the aliphatic side chain, arid mechanisms of formation based on scission of molecules to radical intermediates and re-synthesis are proposcd. The highest yields of the carcinogenic hydrocarbons 3,4-benzopyrene and 3,4-benzofluoranthene were obtained from butylbenzene.

The effects of pressure on the yields of polycyclic aromatic hydrocarbons produced during the supercritical pyrolysis of toluene

“…2-8 also reveal some results peculiar to the high-pressure toluene pyrolysis environment. For example, unlike results observed for toluene [17] or other fuels [28][29][30][31] at atmospheric pressure, Fig. 3 reveals that in the supercritical toluene experiments, yields of anthracene exceed those of its C 14 H 10 isomer phenanthrene.…”

“…Future plans to combine toluene with other components will contribute to a better understanding of fuels that are more complex mixtures. Gas-phase toluene pyrolysis has been investigated by several researchers [16][17][18][19], but little is known about the pyrolysis of toluene under supercritical conditions. Likewise, most research on PAH formation pertains to the gas phase [20][21][22][23][24][25][26][27][28][29][30][31][32][33][34][35]; little has been done under supercritical conditions.…”

An extended mechanism including high pressure conditions (700bar) for toluene pyrolysis

“…These results were confirmed and completed in later publications as for instance Takahasi [5], Badger and Spotswood [6], Errede and Cassidy [7], Hurd and Macon [8] and Brooks et al [9]. It was shown that the benzene produced is generated by the ipso addition of hydrogen atom on toluene, leading to the release of a methyl group which then generates methane [9].…”

Computational Study on the Unimolecular Decomposition of JP-8 Jet Fuel Surrogates III: Butylbenzene Isomers (n-, s-, and t-C14H10)

“…35 Early pyrolysis experiments on n-butylbenzene followed by the chromatographic detection of aromatic hydrocarbons also proposed radical-initiated chain reactions. 36 The involvement of radical transient species likewise gained support from Leigh et al′s study in which the authors explored the pyrolysis of n-butylbenzene and detected ethylene, proposing a radical chain mechanism initiated by the dissociation of n-butylbenzene into benzyl and propyl radicals, C 6 H 5 CH 2 CH 2 CH 2 CH 3 → C 6 H 5 CH 2 + CH 2 CH 2 CH 3 , followed by the decomposition of propyl radicals to ethylene and the methyl radical, CH 3 CH 2 CH 2 → CH 3 + C 2 H 4 . 37 Furthermore, Tsang 38 studied the pyrolysis of t-butylbenzene, suggesting the existence of C 4 H 9 and C 6 H 5 transient radicals.…”