Presoot and Soot Formations in Heating of Hydrocarbon Fuels

Abstract

The soluble and insoluble particles produced in heating the hydrocabon fuel have been measured to study the sooting processes. It is shown that soluble particles called presoot in this paper can be regarded as the "precursors", composed of heavy hydrocarbon droplets, and insoluble ones are composed of soot. Methane, propane, ethylene, and acetylene were employed as the fuel. As to the methane, propane, and ethylene, it is shown that presoot are produced in endothermic reactions and the overall activation energies are detemined from the Arrhenius plots of yields. In the case of acetylene, the reaction of soot formation is exothermic and presoot is not observed, because it grows into soot as soon as it forms by self-generating heat. Furthermore, it is shown that the effects of oxygen on both the presoot and soot formations are hardly detected and that the effective factors of fuel property are both the C/H ratio and the enthalpy of formation.