Carbon black oxidation in the presence of Al2O3, CeO2, and Mn oxide catalysts:: An EPR study

Carbon black oxidation in the presence of CeO2, Al2O3 and manganese oxide catalysts has been studied in tight contact conditions. In the presence of manganese based catalysts, the temperature gain is about 275 degrees C compared to the non-catalysed carbon black oxidation. The contribution of the manganese species to enhance the reactivity of carbon black oxidation has been evaluated by EPR technique. For Mn/Ce + CB mixtures the Mn2+ content considerably increases consequently to tight milled treatment indicating the reduction of some manganese species with higher oxidation states into Mn2+ ions. This phenomenon can be considered as the first step in the carbon black oxidation mechanism in the presence of Mn/Ce catalysts. (c) 2006 Elsevier B.V. All rights reserved.