Praseodymium effects on greatly improving low-temperature hydrothermal stability of Cu/SAPO-34 NH_(3)-SCR catalysts  

作　　者：Xiaojie Yu a Xinyu Li Chen Wang Jianqiang Wang Meiqing Shen 

机构地区：[1]m.4.tarikul islam 2,gurong shenschool of materials science and engineering,tianjin university,tianjin,300350,china [2]school of chemical engineering and technology,tianjin university,tianjin,300350,china [3]school of environmental and safety engineering,north university of china,taiyuan,030051,china [4]national rare earth catalysis research institute,dongying,257000,china

出　　处：《Journal of Rare Earths》2025年第4期707-718,I0003,共13页稀土学报(英文版)

基　　金：supported by the National Key R&D Program of China(2021YFB3503200);the Innovative Research Groups of the National Natural Science Foundation of China(51921004);Young Elite Scientists Sponsorship Program by CAST(2021QNRC001);the Key R&D project of Shandong Province(2021CXGC010703,2022CXGC020311)。

摘　　要：Based on the previous findings that the presence of hydroxyl groups on the outer surface is crucial for maintaining skeletal stability,we propose a strategy modified Cu/SAPO-34 using Pr ions in this study.Therefore,we conducted several measurements to investigate the effect of Pr ions on the lowtemperature hydrothermal stability of Cu/SAPO-34.We find that Pr exists only on the surface of Cu/SAPO-34 as ions and oxides,with Pr^(3+)ions playing a protective role in occupying surface acidic sites.The addition of small amounts of Pr leads to the re-dispersion of Cu,resulting in improved lowtemperature selective catalytic reduction(SCR)activity in the as-synthesized samples.Furthermore,it enhances the resistance to decomposition of the Si-(OH)-Al framework during low-temperature hydrothermal aging,thereby preserving the framework structure and allowing detached active Cu species to return to exchangeable positions,ultimately restoring SCR activity.However,as the Pr content increases,the enhanced acidity causes some structural damage,gradually weakening the protective effect.Our work demonstrates that Pr modification is a simple and effective solution to the issue of poor lowtemperature hydrothermal stability in Cu/SAPO-34,providing a promising way for the application of light rare earth elements.

关 键 词：NH_(3)-SCR Pr modification Cu/SAPO-34 Low-temperature hydrothermal stability Rare earths 

分 类 号：O643.36[理学—物理化学]