Ce-or La-doped Cu/SSZ-13 catalysts were prepared by a hydrothermal method and Cu,Ce or La ions were incorporated through stepwise ion exchange,The catalyst activity was measured for the ammonia selective catalytic red...Ce-or La-doped Cu/SSZ-13 catalysts were prepared by a hydrothermal method and Cu,Ce or La ions were incorporated through stepwise ion exchange,The catalyst activity was measured for the ammonia selective catalytic reduction reaction.The structure and composition of catalyst were characterized by using X-ray diffraction,scanning electron microscopy,inductively coupled plasma mass spectrometry solid-state NMR,NH_(3)-TPD techniques,and the active components were examined by XPS and XANES.The results indicate that the Ce and La doping can both completely preserve the SCR activity of Cu/SSZ-13 above 300℃,but there is also a decrease of activity below 200℃.On the other hand,Ce doping is beneficial to the formation of framework aluminum,stabilizes molecular sieve framework and Cu active sites of Cu/SSZ-13,thereby improves the catalyst hydrothermal stability.But La doping will decrease the amount of framework aluminum and Cu active sites of Cu/SSZ-13 after hydrothermally aging,even destroy zeolite CHA structure.This is quite harmful to the catalyst hydrothermal stability.展开更多
基金the National Natural Science Foundation of China(21676288,21773230)Dalian National Laboratory for Clean Energy(DNL)Cooperation Fund,CAS(DNL 180406)+1 种基金QIBEBT(QIBEBT ZZBS 201805)Liaoning Revitalization Talents Program(XLYC1807207)。
文摘Ce-or La-doped Cu/SSZ-13 catalysts were prepared by a hydrothermal method and Cu,Ce or La ions were incorporated through stepwise ion exchange,The catalyst activity was measured for the ammonia selective catalytic reduction reaction.The structure and composition of catalyst were characterized by using X-ray diffraction,scanning electron microscopy,inductively coupled plasma mass spectrometry solid-state NMR,NH_(3)-TPD techniques,and the active components were examined by XPS and XANES.The results indicate that the Ce and La doping can both completely preserve the SCR activity of Cu/SSZ-13 above 300℃,but there is also a decrease of activity below 200℃.On the other hand,Ce doping is beneficial to the formation of framework aluminum,stabilizes molecular sieve framework and Cu active sites of Cu/SSZ-13,thereby improves the catalyst hydrothermal stability.But La doping will decrease the amount of framework aluminum and Cu active sites of Cu/SSZ-13 after hydrothermally aging,even destroy zeolite CHA structure.This is quite harmful to the catalyst hydrothermal stability.
基金Guizhou Province Ordinary Colleges and Universities Youth Science and Technology Talent Growth Project (Grant No. QJH-KY[2022]249, QJH-KY[2022]250)Science and Technology Fund of Guizhou Provincial Health Commission (Grant No. GZWKJ2022-464 and GZWKJ2022-466)+5 种基金the Basic Research Program of Guizhou Province,Guizhou Provience Science and Technology Foundation,China (Grant No. QKHJC-ZK[2021]YB553, QKHRCZK[2023]YB308, and QKHJC-ZK[2023]ZD035)Cultivation Project of National Natural Science Foundation of Guizhou Medical University (Grant No. 20NSP052)The Start-up Foundation for Doctors of Guizhou Medical University (Grant No. YJ2020-BK035)Provincial College Student Innovation,Entrepreneurship Training Program (Grant No. S202010660142)the Guizhou Provincial Scientific and Technologic Innovation Base (Grant No.[2023]003)the National Natural Science Foundation of China (Grant No. 22307026)。