Influence of selected metal oxides on the oxidation kinetics of graphite

Abstract The thermal decomposition of graphite in air was studied in detail by thermogravimetry in the presence of varying concentrations of U 3 O 8 , CeO 2 and ThO 2 . The decomposition was found to follow first-order kinetics with a significant decrease in decomposition temperatures and activation energies, E , due to presence of the oxides. There was a decrease in log A , associated with a decrease in E , indicating the kinetic compensation effect. One of the possible mechanisms for catalysis, namely localized reduction of the oxide by graphite followed by reoxidation of the lower oxide by air, is not supported by the results obtained.