Comparison of Nanocrystalline and Polycrystalline Oxide Supports for Catalytic Oxidation of Methane

Abstract

ABSTRACTNanocrystalline and polycrystalline ZrO2, CeO2 and Mn3O4 without and with 5 wt% Pd have been tested for methane oxidation. The nanocrystalline catalysts perform better than the polycrystalline catalysts on a weight basis. Nanocrystalline (n)-CeO2 performs much better than n-ZrO2, and both perform much better than polycrystalline (P)-CeO2 and P-ZrO2. 5 wt% Pd/n-ZrO2 is the best catalyst tested, but 5 wt% Pd/n-CeO2 performs nearly as well. A 20 wt% Ag/p-ZrO2 and a 20 wt% Ag/n-ZrO2 catalyst were also tested. The Ag yields a significant improvement over the bare supports, but not as much so as Pd.