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The surface property of activated carbon is modified by nitric acid and urea. The effect of surface property of activated carbon on denitration and sulfur resistance performance of supported cerium based catalyst is studied. N, adsorption-desorption, XRD and XPS technologies are used to characterize the structure and performance of catalysts. The results show that activity and sulfur resistance performance are related to surface acidity, the type and quantity of surface functional groups. After the activated carbon is pretreated with nitric acid, the surface acidity, interaction between activated carbon and CeO2 are improved. Accordingly, the dispersity of CeO2, the ratio of surface adsorbed oxygen and Ce3+ are also increased, significantly enhancing de-NOI and anti-SO2 performance of catalysts. The amount of oxygen and N-6 basic functional groups are increased after treated by urea. A large amount of oxygen and N-6 functional groups lead to increase of unstable groups and surface acidity of activated carbon, respectively. The combination of the two factors weaken the interaction between activated carbon and CeO2 resulting in decline of CeO2 dispersity, Ce3+ ratio and surface adsorbed oxygen. At last, activity and sulfur resistance performance of catalysts are descended. [ABSTRACT FROM AUTHOR]

CeO2/AC catalyst doped with MnOx was prepared by impregnation method. The influence of MnOx doping on NH3 selective catalytic reduction of NOx at low temperature was investigated. X-ray diffraction (XRD)，NH3 temperature programmed desorption (NH3-TPD) and H2-temperature programmed reduction (H2-TPR) were used to evaluate structure and performance of catalyst. The result showed that MnOx doping improved the surface acidity and redox property of the catalysts - which enhanced the catalytic activity lower than 110􀀀C • But the catalytic activity higher than 120 °C decreased with the increasing doping content of MnOx. The catalyst with m (Ce)/m (Mn) ratio of 4 J 1 shows better activity than the other catalyst in the whole temperature range. It also behaved excellent sulfur resistance performance at 210􀀀C. [ABSTRACT FROM AUTHOR]