Kinetic modelling of the oxidation of a wide range of carbon materials

A kinetic study of the oxidation of carbon materials and an analysis of their differing reactivities are presented. Oxidation experiments of diesel soot and graphite were carried out and kinetics-limited oxidation experiments of graphite and a range of low-mineral graphitic carbons – a carbon black, ethylene flame soot, diesel soot and coke – were modelled. The experiments allowed for calibration of a three-step semi-global surface mechanism for each of the materials. The surface description and coupled reactor model are capable of reproducing experiments at different temperature regimes and reactor configurations. Kinetic parameters ki are expressed in terms of carbon content. Activation energies in particular, increase with carbon content. The values of ki enclose intrinsic reactivity effects due to the degree of crystallinity and surface chemistry (RSA/TSA).

► Semi-global kinetic parameters of carbon oxidation.
► Kinetic parameters indicative of the nature of carbonaceous materials.
► Oxidation activation energies increase linearly with carbon content.
► Dependence of pre-exponential factors and CO/CO2 on carbon nature is non linear.