CO oxidation over CuO/Ce1鈭?/sub>xCuxO2鈭?/sub>未 and Ce1鈭?/sub>xCuxO2鈭?/sub>未 catalysts: Synergetic effects and kinetic study
- 作者：Ai-Ping Jia ; Geng-Shen Hu ; Lian Meng ; Yun-Long Xie ; Ji-Qing Lu ; jiqinglu@zjnu.cn ; Meng-Fei Luo ; mengfeiluo@zjnu.cn
- 关键词：CO oxidation ; CuO/Ce1&minus ; xCuxO2&minus ; 未 catalysts ; Synergetic effects ; Kinetics ; Mars&ndash ; van Krevelen mechanism
- 刊名：Journal of Catalysis
- 出版年：2012
- 期刊代码：97_00219517
- 类别：ce
- 出版时间：May, 2012
- 卷：289
- 期：Complete
- 页码：199-209
- 文件大小：1133 K
摘要
A series of CuO/Ce1鈭?/sub>xCuxO2鈭?/sub>未 catalysts were prepared, and corresponding Ce1鈭?/sub>xCuxO2鈭?/sub>未 catalysts were obtained with nitric acid treatment. X-ray diffraction and Raman spectroscopic results revealed the presence of surface CuO species and CuxCe1鈭?/sub>xO2鈭?/sub>未 solid solution in the catalysts. CO oxidation testing found that the CO conversion was proportional to the concentrations of chemisorbed CO and oxygen vacancies in the CuO/Ce1鈭?/sub>xCuxO2鈭?/sub>未 catalysts, suggesting synergetic effects of the surface CuO species and CuxCe1鈭?/sub>xO2鈭?/sub>未 solid solution on the reactivity, as the former provided sites for CO chemisorption and the latter promoted reducibility of the catalyst for oxygen activation. Kinetic studies showed that the apparent activation energy was 42 kJ mol鈭? for CuO/Ce1鈭?/sub>xCuxO2鈭?/sub>未 and 95 kJ mol鈭? for Ce1鈭?/sub>xCuxO2鈭?/sub>未. The power-law rate expression was for CuO/Ce1鈭?/sub>xCuxO2鈭?/sub>未 and for the Ce1鈭?/sub>xCuxO2鈭?/sub>未 catalyst, indicating that the reaction pathway followed a Mars-van Krevelen type mechanism.