Modelling of Carbon Black oxidation in the presence of CeO2 catalyst using a 3D representation of the solid–solid mixture

Abstract

A model based on a 3D representation of mixtures involving Carbon Black (CB) and commercial ceria (CeO2) particles placed in a fixed bed reactor is proposed. Catalyst particles may aggregate in different ways in the whole bed and different CB–CeO2 mass ratios are considered which range from 95–5 to 10–90. Two types of oxidation are assigned by the model: a catalytic oxidation under the influence of CeO2 and a non-catalytic one in the other case. The activation energies of these oxidation processes have been determined through experiments, while their frequency factors are derived for the two reactions using a numerical simulation. The model simulates the CB oxidation in a good way whatever the CB–CeO2 mass ratio, except for the 50–50 case. The catalytic oxidation is here underestimated, as the contact between CB and CeO2 is progressively lost.