Unraveling the nature of cerium on stabilizing Cu/SAPO-34 NH_(3)-SCR catalysts under hydrothermal aging at low temperatures  

作　　者：Weibo Zhang Meiqing Shen Jun Wang Xinyu Li Jianqiang Wang Gurong Shen Chen Wang 

机构地区：[1]School of Chemical Engineering&Technology,Tianjin University,Tianjin,300072,China [2]National Rare Earth Catalysis Research Institute,Dongying,257000,China [3]School of Materials Science and Engineering,Tianjin University,Tianjin,300072,China [4]School of Environmental and Safety Engineering,North University of China,Taiyuan,030051,China

出　　处：《Journal of Rare Earths》2023年第10期1551-1561,I0003,共12页稀土学报（英文版）

基　　金：the National Natural Science Foundation of China for Youths(21908207);National Key R&D Program of China(2021YFB3503200);the Key R&D project of Shandong Province(2021CXGC010703);China Postdoctoral Science Foundation(2020M670659);Shanxi Province Science Foundation for Youths(201901D211224);Scientific and Technological Innovation Programs of Higher Education Institutions in Shanxi(2019L0575)。

摘　　要：To reveal how cerium stabilizes Cu/SAPO-34 at low-temperature hydrothermal aging,various amounts of cerium were introduced into Cu/SAPO-34 via impregnation method and treated at 70℃with RH 80%for 96 h.Cerium as Ce^(3+)and CeO_(2)nanoparticle is located on the surface of Cu/SAPO-34,and Ce^(3+)plays a vital role on gradually decreasing surface acidity and blocking defect sites with an increase of Ce loading.After hydrothermal aging,Cu/SAPO-34 with high Ce loading shows the superior SCR activity comparable to fresh samples.It is proven that the surface acidity determines the stability of the structure during hydrothermal aging process,and lower surface acidity prevents the number of Cu(Ⅱ)ions from decreasing significantly.Furthermore,the structure's stability helps the recovery of Cu(Ⅱ)ions and renders an outstanding regene ration ability.Our finding paves the way for the design of new Cu/SAPO-34catalysts with good SCR activity and long-term stability in real application.

关 键 词：Cu/SAPO-34 NH_(3)-SCR catalysts Low-temperature hydrothermal aging Cerium loading Surface acidity Long-term stability Rare earths 

分 类 号：X701[环境科学与工程—环境工程] TQ426[化学工程]