Selective catalytic reduction of NO by C_2H_2 over Ce-Al_2O_3 catalyst with rate-determining step of NO oxidation  

作　　者：Suhua Yan Xinping Wang Wenchen Wang Zequn Liu Jiahao Niu 

机构地区：[1]State Key Laboratory of Fine Chemicals,Dalian University of Technology,Dalian 116024,Liaoning,China

出　　处：《Journal of Natural Gas Chemistry》2012年第3期332-338,共7页天然气化学杂志（英文版）

基　　金：supported by the National Natural Science Foundation of China (Grant No. 20833011 and 20877015);the State Hi-tech Research and Development Project of the Ministry of Science and Technology of China (Grant No. 2008AA06Z319)

摘　　要：Ce-A12O3 catalysts prepared by co-precipitation are investigated both in NO oxidation by 02 and in selective catalytic reduction of NO by C2H2 （C2H2-SCR）. It is found that C2H2-SCR is initiated and controlled by NO oxidation to NO2 over A12O3. Ce loading on A12O3 is almost inactive for NO oxidation below 350℃, since NO2 strongly adsorbs on cerium oxide, leading to the active sites being blocked, which was characterized by temperature-programmed desorption of NO and NO2 and Fourier transform infrared spectroscopy after NO＋O2 coadsorption over the samples. However, in the case of C2H2-SCR, Ce loading on A1203 significantly improves the reaction by accelerating the NO oxidation step in the temperature range of 250-450℃, since the nitrate species produced by NO2 adsorption is an active intermediate required by C2H2-SCR.Ce-A12O3 catalysts prepared by co-precipitation are investigated both in NO oxidation by 02 and in selective catalytic reduction of NO by C2H2 （C2H2-SCR）. It is found that C2H2-SCR is initiated and controlled by NO oxidation to NO2 over A12O3. Ce loading on A12O3 is almost inactive for NO oxidation below 350℃, since NO2 strongly adsorbs on cerium oxide, leading to the active sites being blocked, which was characterized by temperature-programmed desorption of NO and NO2 and Fourier transform infrared spectroscopy after NO＋O2 coadsorption over the samples. However, in the case of C2H2-SCR, Ce loading on A1203 significantly improves the reaction by accelerating the NO oxidation step in the temperature range of 250-450℃, since the nitrate species produced by NO2 adsorption is an active intermediate required by C2H2-SCR.

关 键 词：NOx removal NO oxidation nitrate species Ce-A1203 ACETYLENE 

分 类 号：O643.36[理学—物理化学] X701[理学—化学]