Promotional mechanism of activity of CeEuMnO_(x) ternary oxide for low temperature SCR of NO_(x)  

作　　者：Qiji Wang Yanhua Wang Liehao Wei Kaixin Wang Caixia Liu Degang Ma Qingling Liu 

机构地区：[1]Tianjin Key Laboratory of Indoor Air Environmental Quality Control,School of Environmental Science and Engineering,Tianjin University,Tianjin 300350,China [2]State Key Laboratory of Engines,Tianjin University,Tianjin 300072,China

出　　处：《Journal of Rare Earths》2023年第6期965-974,I0006,共11页稀土学报（英文版）

基　　金：Project supported by the National Key R&D Program of China(2019YFC1904100,2019YFC1904102,2019YFC1903900,2019YFC1903902);the National Natural Science Foundation of China(U20A20132,52106180,22076136);the Hebei Province Major Scientific and Technological Achievement Transformation Fund Support Project(2021004012 A);the Central Government Guides the Local Science and Technology Development Fund Project(206Z3702G).

摘　　要：Due to strong synergistic effect of the elements,a series of XEuMnO_(x) ternary oxides(X=Ce,Ni,Co,Sb,Sn,Mo) were synthesized by one-pot co-precipitation method,and composite components were identified and optimized to maintain high activity and superior SO_(2)and H_(2)O endurance in selective catalytic reduction of NO_(x)with NH_(3)(NH_(3)-SCR).NO_(x)conversion of CeEuMnO_(x) ternary oxide catalysts attains more than 90% at 100-250℃,and finally achieves 74%under existence of 50×10^(-6)SO_(2) and 10 vol% H_(2)O at 230℃.The facile electron transfer through redox cycle of Mn^(3+)+Ce^(4+)■Mn4++Ce^(3+) and enhanced oxygen mobility can promote formation of more Mn species in high oxidation state and chemisorbed oxygen,accelerating oxidation of NO and the adsorbed NO_(2) formed can facilitate"fast SCR"reaction to improve low-temperature activity.In situ diffuse reflectance infrared Fourier transform spectroscopy(DRIFTS)study reveals that addition of Ce to EuMnO_(x)catalyst boosts adsorption of NH_(3)and NO_(x)species.NH_(3)species are activated as crucial intermediate(NH_(2))to promote NH_(3)-SCR reaction.This research provides a novel material for practical deNO_(x)application of stationary source combustion flue gas in the future.

关 键 词：NH3-SCR CeEuMnO_(x)ternary oxide Lowetemperature activity In situ DRIFTS Rare earths 

分 类 号：X701[环境科学与工程—环境工程] TQ426[化学工程]