Soot Formation During Pyrolysis and Oxidation of Aliphatic and Aromatic Hydrocarbons in Shock Waves: Experiments and Detailed Kinetic Modeling

Abstract

Experimental and kinetic modeling studies of soot formation in the pyrolysis and oxidation of various mixtures of aliphatic and aromatic hydrocarbons in argon were carried out for shock tube conditions. The soot yield and the soot particle temperature were determined using the double-beam absorption-emission technique. Our previous kinetic model of soot formation is augmented by introducing an additional subset of reactions of soot nucleation, involving both polyaromatic and unsaturated aliphatic hydrocarbons. The proposed kinetic model was successfully tested by describing the published data on the products yield in the pyrolysis and oxidation of acetylene and diacetylene in shock-tube experiments. It closely reproduces our experimental data on the time histories of the soot yield and soot particle temperature, as well as the temperature and concentration dependences of the soot yield at fixed reaction times, for the pyrolysis and oxidation of C2H2/Ar, C2H6/Ar, C2H4/Ar, C2H4/O2/Ar, CH4/Ar, CH4/O2/Ar, C3H8/Ar, C3H6/Ar, toluene/Ar, and benzene/Ar mixtures under fuel rich conditions in reflected shock waves (T50 = 1400–2850 K, P50 = 2.5–5.5 bar).