Kinetic Analysis of O₂- and NO₂-Based Oxidation of Synthetic Soot

Abstract

This study demonstrates the application of two different methods to evaluate the kinetics of O-2- and NO2-based oxidation of carbonaceous matter. The influence of reactor setup and experiment execution on the accuracy and interpretation of the kinetic parameters is also discussed. The fundamental difference between the two methods lies in how rate changes during the progress of oxidation are interpreted: by changes in the fraction of atoms available for reaction (traditional approach) or by changes in the activation energy (unconventional approach). Using the traditional approach, it was found that two parallel reactions with a first-order reaction model and a third-order Avrami-Erofeyev model could accurately reproduce the O-2-based oxidation curves. The same model (with a different set of parameter values) could also describe the NO2-based kinetics. The unconventional method also provided an accurate representation of the data and can thus function as a complementary evaluation method.