Chemical Engineering & Technology, Vol.27, No.6, 687-693, 2004
Total oxidation of methane and chlorinated hydrocarbons on zirconia supported A(1-x)Sr(x)MnO(3) catalysts
The catalytic behavior of ZrO2 and ZrO2 containing 8 mol-% Y2O3 supported A(1-x)Sr(x)MnO(3) (A= La, didymium) perovskites was studied in the total oxidation of methane, chloromethane and dichloromethane considering catalyst deactivation and by-product formation. The perovskites are dispersed on the support surface; clusters with a perovskite-like structure were formed. The supported catalysts are characterized by higher specific surface areas compared with the unsupported ones. Partial substitution of A-site cations by Sr leads to an enhancement of the catalytic activity in the total oxidation of methane, but not in the total oxidation of chlorinated hydrocarbons (CHC). The catalytic activity of supported and unsupported catalysts is comparable in the total oxidation of methane in spite of the significantly lower perovskite content of the supported catalysts. In the CHC conversion the catalytic activity of the supported catalysts is higher than that of the unsupported ones.