Promotion Effects of Metal Oxides on the Ag/Al₂O₃ Catalysts for Selective Catalytic Reduction of NO with C₃H₆

Abstract

The transition-metal oxide(ZrO2, Fe2O3) and rare earth-metal oxide(La2O3, CeO2) promoted Ag/Al2O3 catalysts for selective catalytic reduction of NO by C3H6 were investigated. These catalysts were characterized by temperature programmed desorption of NO and O2 (NO-TPD and O2-TPD), N2 adsorption/desorption isotherms (BET), and X-ray diffraction (XRD) techniques, respectively. The BET result indicates the ZrO2 promoted sample possesses larger surface area, and the TPD analysis demonstrates the dispersity and amount of adsorbed NO and O2 are improved, both the results are favorable for the catalytic activity, which can be attributed to the synergic interaction between zirconia promoter and alumina support shown in the XRD pattern.