High pressure auto-ignition and oxidation mechanisms of o-xylene, o-ethyltoluene, and n-butylbenzene between 600 and 900 K

摘要: Abstract A complex phenomenology of auto-ignition, similar to n -alkanes and -alkenes, has been revealed between 600–900 K at pressures above 14 bar by studying in a rapid compression machine stoichiometric mixtures o -xylene ( -methyltoluene), -ethyltoluene, or -butylbenzene oxygen with lower concentrations than air. Extensive chemical analyses the reacting before ignition were performed elucidate mechanisms reaction. The classical low temperature scheme, modified for reactivities benzylic-type hydrogen atoms radicals, is valid. It appears that addition molecular radicals leads double peroxidation branching only when transfer isomerization step occurs either from an ortho-alkyl group, another carbon atom same alkyl chain. products observed are shown be consistent proposed mechanism. pattern auto-ignition found, not -xylene, -butylbenzene, but also 1,2,3-trimethylbenzene, 1,2,4-trimethylbenzene, -propylbenzene, ethylbenzene. When easily transferable available selective such as peroxy through completely different pathways, which require higher temperatures pressures. Then, much simpler, already toluene, m p 1,3,5-trimethylbenzene [1] .