The Effect of SO2 and Ca Co-pretreatment on the Catalytic Activity of Mn–Ce/TiO2 Catalysts for Selective Catalytic Reduction of NO with NH3

Abstract

Mn–Ce/TiO2 catalysts were co-pretreated with SO2 and Ca and applied for the selective catalytic reduction (SCR) of NO with ammonia. The effect of co-pretreatment of SO2 and Ca on the physicochemical properties of catalysts was investigated by BET, XRD, XPS, NH3-TPD, H2-TPR, and UV–Vis techniques. The results show the co-pretreatment of SO2 and Ca greatly influences the physicochemical properties of catalysts such as texture characteristics, surface acidity and redox ability, amounts of active species and surface OH group, and therefore affects the catalytic activity of catalysts. The Mn–Ce–Ti(S–OH) catalyst co-pretreated with SO2 and Ca(OH)2 exhibits better catalytic activity than Mn–Ce–Ti(S–Cl) catalyst co-pretreated with SO2 and CaCl2. The Mn–Ce–Ti(S–OH) catalyst possesses larger specific surface area, higher concentrations of surface active species and surface chemisorbed oxygen, better surface acidity and redox ability, which may contribute to the accelerated catalytic activity.