物理化学学报2012，Vol.28Issue(3)：681-685,5.DOI:10.3866/PKU.WHXB201111141
NO选择性催化还原Ce-Mn-Ti-O催化剂铈组分助催化作用
Promotional Effect of Cerium Oxide on the Catalytic Properties of Ce-Mn-Ti-O Catalysts for Selective Catalytic Reduction of NO
庄柯 1裘婧 1许波连 1范以宁1
作者信息
- 1. 南京大学化学化工学院,介观化学教育部重点实验室,江苏省机动车尾气污染控制重点实验室,南京210093
- 折叠
摘要
Abstract
The promotional effect of cerium oxide on the catalytic properties of Ce-Mn-Ti-0 composite oxide catalysts prepared by the sol-gel method was studied using NH3-temperature programmed desorption (NH3-TPD), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), H2-temperature programmed reduction (H2-TPR), and BET surface area measurements combined with microreactor tests of NO selective catalytic reduction (SCR). The results showed that the addition of a cerium oxide component remarkably increased the low-temperature SCR activity of Mn-Ti-0 composite oxide catalyst. When the cerium content was increased, NO conversion increased significantly and reached a maximum around Ce/Mn molar ratio of 0.08. Further increases in the cerium content resulted in a decrease in NO conversion over the catalyst. The experimental results indicated that the addition of a cerium oxide component does not influence the surface acidity of Mn-Ti-0 composite oxide catalyst, but increases the surface concentration of catalytically active Mn species, the relative content of Mn4*, and the reducibility of Mn species, leading to an increase in the SCR activity of Ce-Mn-Ti-O composite oxide catalysts. When the Ce/Mn molar ratio was greater than 0.08, the formation of amorphous multilayer Ce-O-Mn species composed of Ce and Mn species may reduce the Mn/Ti molar ratio and the reducibility of Mn species, leading to a decrease in the SCR activity of Ce-Mn-Ti-0 composite oxide catalysts.关键词
氧化铈/氧化锰/氧化钛/氮氧化物/选择性催化还原Key words
Cerium oxide/Manganese oxide/Titania/Nitric oxide/Selective catalytic reduction分类
化学化工引用本文复制引用
庄柯,裘婧,许波连,范以宁..NO选择性催化还原Ce-Mn-Ti-O催化剂铈组分助催化作用[J].物理化学学报,2012,28(3):681-685,5.
