Effects of Doping Metal on the Carburization of MoO3/Al2O3

The investigation on MoO3 / Al2O3 sample or its modifiers with nickel，copper or potassium was performed using temperature programmed surface reaction（TPSR）technique and measurements of BET surface area. The results indicate that addition of nickel promotes the methane reduction，further the carburization，of MoO3，and addition of nickel also promotes the activation of methane over the surface of oxycarbide or carbide due to the increase of active sites per unit area and intrinsic activity of catalytic centers. This is favorable to the conversion of methane. The addition of copper promotes the methane reduction，further the carburization，of MoO3 to some extent，while the introduction of copper also accelerates the sintering of catalyst to a degree. Thus copper doped carbide catalyst exhibits its exceptionally catalytic performance. However，potassium prevents the MoO3 from reduction with methane，which is unfavorable to the carburization. Potassium also restrains methane from being activated over the surface of oxycarbide or carbide. MoO3 / Al2O3 doped with potassium is of lower specific area，which originates from its boosting sintering of catalyst. This caauses the inferior methane conversion over potassium doped carbide catalyst.