Deactivation induced by metal sulfate over MnCeOx catalyst in NH_(3)-SCR reaction at low temperature  

作　　者：Qiao Xie Dongqi An Linsen Zhou Tingzhen Li Zhenghua Hu Menghan Chen Menglan Ma Lei Zhang Jingfang Sun Lin Dong 

机构地区：[1]School of Environmental and Chemical Engineering,Chongqing Three Gorges University,Chongqing,404000,China [2]Key Laboratory of Water Environment Evolution and Pollution Control in the Three Gorges Reservoir,Chongqing Three Gorges University,Chongqing.404000,China [3]Jiangsu Key Laboratory of Vehicle Emissions Control,Center of Modern Analysis,School of Environment,Nanjing University,Nanjing,210093,China [4]Institute of Materials,China Academy of Engineering Physics,Mianyang,621908,China

出　　处：《Journal of Rare Earths》2024年第6期1056-1065,I0002,共11页稀土学报（英文版）

基　　金：Project supported by the National Natural Science Foundation of China(21607019);the Scientific andTechnological Research Program of Chongqing Municipal Education Commission(KJQN202101242,KJQN202001227);the Science andTechnology Project of Wanzhou(wzstc-2019034);the Open Project Program of Key Laboratory of Water Environment Evolution andPollution Control in the Three Gorges Reservoir(WEPKL2019ZD-04);the Project Program of Chongqing Postgraduate Research andInnovation(CYS21489)。

摘　　要：Sulfate adsorption is one of the factors that cause the poisoning of catalyst in the low-temperature NH_(3) selective catalytic reduction reaction(NH_(3)-SCR).In this paper,by controlling the co-adsorption time of SO_(2) and O_(2) at 150℃,a range of sulfated MnCeOx catalysts with different contents of metal sulfate species were prepared to reveal the influence of metal sulfate species content on the catalytic performances and reaction mechanisms at low temperature.The catalytic activity below 250℃rapidly decreases with increasing metal sulfate species content.The results of characterizations shed light on the reduction of specific surface area,Mn^(4+)and Ce^(3+)content,and redox ability of MnCeOx owing to the formation of metal sulfate species.Further experiments reveal that metal sulfate species preferentially absorb on MnOx domains rather than on CeO_(2) domains,and the adsorbed metal sulfate species can suppress the Eley-Rideal and the Langmuir-Hinshelwood reaction mechanisms over the sulfated MnCeOx.All the above results are detrimental to the activity of sulfated MnCeOx in the low-temperature NH3-SCR reaction.

关 键 词：NH_(3)selective catalytic reduction MnCeOx catalyst SULFATION Low-temperature activity SO_(2)poisoning Rare earths 

分 类 号：TQ426[化学工程]