The adsorption of CO2 and NO on supported Pd catalysts has been studied by using TPD-MS method and the adsorbed surface species were discussed based on literatures. The amount and intensity of basic sites increase whe...The adsorption of CO2 and NO on supported Pd catalysts has been studied by using TPD-MS method and the adsorbed surface species were discussed based on literatures. The amount and intensity of basic sites increase when promoter Li is added, whereas the amount of basic sites decreases when Ce is added. It is found that there are three kinds of basic sites with different intensity on the catalyst surface. On sample Pd/Al2O3 and Pd/Al2O3-Li2O, large amount of CO desorption species is detected, this shows some CO2 on the surface being decomposed. There is no such effect on the sample Pd/Al2O3-CeO2. After analyzing the TPD profiles of NO adsorption on catalysts, it is found that both the NO desorption amount and the shapes of desorption peaks change remarkably when promoter Li or Ce is added. In the case of Li, the γ-peak （nitrate and nitrite species on surface） of NO desorption increases, the intermediate N2O desorbs at higher temperature. In the case of Ce, the α-peak （species on the Bronstesd acidic sites ） of NO desorption decreases, and N2O desorbs at lower temperature.展开更多
基金supported by the National Natural Science Foundation of China (50772107)National Key Basic Research Program of China (973)(2007CB210206)National High-Tech Research and Development Program of China (863) (2009AA05Z435)~~
基金The project was supported by the National Natural Science Foundation of China (50772107)National Key Basic Research Program of China (973)(2007CB210206)National High-Tech Research and Development Program of China (863) (2009AA05Z435)~~
文摘The adsorption of CO2 and NO on supported Pd catalysts has been studied by using TPD-MS method and the adsorbed surface species were discussed based on literatures. The amount and intensity of basic sites increase when promoter Li is added, whereas the amount of basic sites decreases when Ce is added. It is found that there are three kinds of basic sites with different intensity on the catalyst surface. On sample Pd/Al2O3 and Pd/Al2O3-Li2O, large amount of CO desorption species is detected, this shows some CO2 on the surface being decomposed. There is no such effect on the sample Pd/Al2O3-CeO2. After analyzing the TPD profiles of NO adsorption on catalysts, it is found that both the NO desorption amount and the shapes of desorption peaks change remarkably when promoter Li or Ce is added. In the case of Li, the γ-peak （nitrate and nitrite species on surface） of NO desorption increases, the intermediate N2O desorbs at higher temperature. In the case of Ce, the α-peak （species on the Bronstesd acidic sites ） of NO desorption decreases, and N2O desorbs at lower temperature.
基金supported by the Natural Science Foundation of Higher Education of Anhui Province, China (KJ2009B066Z)National Natural Science Foundation of China (20871039, 20673106)~~
