Study on the promoting mechanism of cerium on catalytic oxidation of SO2 over vanadium catalyst.

The vanadium catalysts V/SiO2 and x% Ce-V/SiO2 catalysts were prepared by ultrasonic impregnation method, and characterized by BET and XRD, and investigated the effect of CeO2 on the actual catalytic process of vanadium catalyst through in situ Raman technology. The catalytic activity of SO2 to SO3 were investigated. Results indicated that the introduction of cerium oxide optimizes the pore size dis-tribution of vanadium catalyst, promotes the formation of active substance (Vv O)2 O (SO4) 44-, and improves the valence stability of Vv species, thus avoiding the loss of active species from the molten phase. The 4% Ce-V/SiO2 catalyst improves the SO2 conversion by 11.7% and 30.1% at 450 °C and 425 °C, respectively, compared with V/SiO2 catalyst. And it also maintains the SO2 conversion higher than 90% in the temperature range of 500 ~ 450 °C. [ABSTRACT FROM AUTHOR]