Detailed modeling of carbon oxidation

Artikel i vetenskaplig tidskrift, 2012

The kinetics of low-temperature oxidation of a synthetic carbon black material, i.e. Printex- U, by gaseous oxygen is modeled via conventional mean-field treatment of various detailed reaction schemes as well as lumped models. The significance of different elementary steps is elucidated by comparing predicted CO and CO2 formation during temperature programmed and isothermal carbon oxidation with the corresponding experimental data. In specific the connection between oxidation rate and surface coverages of reaction intermediates is demonstrated. The results suggest that activation of the carbon surface by oxygen adsorption is a key-step for further carbon oxidation and that gas phase oxygen plays a direct role in the formation of CO and CO2. Furthermore, the results suggest that Printex-U is preferably modeled as spherical shaped particles, especially at high conversion stages.