Activities of different metal oxide catalysts on NO reduction and CO oxidation

A series of transition metal oxide catalysts (Zn, Ti, Cu, Ni, Fe and V) supported on Al₂O₃ and SiO2 were prepared using the incipient wetness impregnation method. Their performances on NO reduction and CO oxidation followed the sequence of TiO₂ > CuO/ZnO > CuO > ZnO. TiO₂ supported on SiO₂ was more active than that on Al₂O₃, while ZnO had the opposite performances. The activities of CuO/Al₂O₃ and ZnO/SiO₂ were both decreased with the calcination temperature increasing because the sintering and agglomerations of catalysts were occurred at high temperature.