CuO-CeO_2-MnO_x/γ-Al_2O_3催化剂选择性催化脱除NO机理研究  

STUDIES ON THE MECHANISM FOR SELECTIVE CATALYTIC REDUCTION OF NO OVER CuO-CeO_2-MnO_x/γ-Al_2O_3 CATALYSTS

作　　者：孙路石[1] 向军[1] 赵清森[1] 石金明[1] 王乐乐[1] 谢天[1] 胡松[1] 

机构地区：[1]华中科技大学煤燃烧国家重点实验室,湖北武汉430074

出　　处：《工程热物理学报》2009年第8期1415-1418,共4页Journal of Engineering Thermophysics

基　　金：国家自然科学基金(No.50776037;No.50721005);国家重点基础研究发展规划项目(No.2006CB200304)

摘　　要：利用溶胶凝胶法制备CuO-CeO_2-MnO_x/γ-Al_2O_3催化剂颗粒,在固定床上测试其催化脱硝活性。CuO-CeO_2-MnO_x /γ-Al_2O_3催化剂在200～450℃范围内脱硝效率保持在70%以上。利用程序升温方法研究了催化剂对NH_3的氧化性能,活性组分负载量增多,加强了催化剂对NH_3氧化性能。红外表征显示NH_3被吸附在催化剂的L酸位和B酸位。NO以多种硝酸盐物种在催化剂表面吸附。吸附态NH_3参与SCR反应,但吸附态NO物种仅部分参加SCR反应。AbstractCuO-CeO2-MnOx/r-Al2O3 granular catalysts were synthesized by the sol-gel method. Performance of the CuO-CeO2-MnOx/r-Al2O3catalyst for the selective catalytic reduction （SCR） was explored in a fixed bed adsorption system. The optimum temperature ranges for SCR of NO over the CuO-CeO2-MnOx/r-Al2O3catalyst samples were 200～450℃. The catalysts maintained nearly 100% NO conversion at 350℃. Preliminary tests were carried out to study the behavior of NH3 over catalyst in the presence of oxygen. The catalysts in this experiment had relatively stronger oxidation property on NH3 which improved the activity at low temperature. NH3＋O2, NO＋O2 adsorption on catalyst and the transient response of NH3 and NO were investigated by the in situ diffuse reflectance infrared transform spectroscopy （DRIFT） to provide insight into the mechanism. It was found that the SCR reaction on the CuO-CeO2-MnOx/r-Al2O3 catalyst proceeded in accordance with the Eley-Rideal mechanism and the Langmuir- Hinshelwood hypothesis at the same time. The adsorbed NO may give some contribution to the highly catalytic activity.

关 键 词：选择性催化还原 溶胶凝胶法 CuO-CeO2-MnOx/r-Al2O3 NH3 NO 

分 类 号：X701[环境科学与工程—环境工程]