Shock tube and modeling study of soot formation during the pyrolysis and oxidation of a number of aliphatic and aromatic hydrocarbons

An experimental and modeling study of soot formation during the shock-tube pyrolysis and oxidation of a number of aromatic and aliphatic hydrocarbons was performed. Hydrocarbons with different chemical structures, both aliphatic (methane, propane, and propylene) and aromatic (benzene, toluene, and ethylbenzene), were tested. The experiments showed that the soot formation during the pyrolysis, even in the presence of small amounts of oxygen, is accompanied by a temperature decrease. A new, essentially modified detailed kinetic model of soot formation is proposed, which was successfully tested by describing the published data on the temporal behavior of a number of key species during the initial stages of pyrolysis and oxidation of a number of hydrocarbons under various conditions. When applied to modeling our experimental data, it closely reproduced the time profiles of the soot yield and temperature for the shock-tube pyrolysis of methane, propane, and propylene, as well as benzene, toluene, and ethylbenzene, two sets of compounds of drastically different natures.