Fe掺杂对La0.9Sr0.1Co1-xFexO3催化剂同时净化NO和碳烟活性规律研究  

Study on simultaneous removal of NO and soot by Fe-doped La0.9Sr0.1Co1-xFexO3 catalyst

作　　者：魏炜 乔智威 李树华 苗梦涵 梁红 彭峰 WEI Wei;QIAO Zhiwei;LI Shuhua;MIAO Menghan;LIANG Hong;PENG Feng(Guangzhou Key Laboratory for New Energy and Green Catalysis,College of Chemistry and Chemical Engineering,Guangzhou University,Guangzhou 510006,Guangdong,China)

机构地区：[1]广州大学化学化工学院能源与催化研究所

出　　处：《化工学报》2019年第12期4654-4663,共10页CIESC Journal

基　　金：国家自然科学基金项目(21576058,21676094)

摘　　要：采用柠檬酸-EDTA络合法制备了纳米钙钛矿催化剂La0.9Sr0.1Co1-xFexO3,催化剂具有较好的同时去除NO和碳烟(soot)催化活性,其中La0.9Sr0.1Co0.7Fe0.3O3展现出最佳的催化活性,其在380.0℃时NO转化率为32.5%,soot最大燃烧速率温度(Tm)为368.5℃。H2-程序升温还原(H2-TPR)和NO-程序升温脱附(NO-TPD)结果表明,Fe掺杂能显著提高催化剂低温还原性能、表面氧物种活性及NO吸附性能,这有利于其改善催化活性。X射线光电子能谱(XPS)结果表明,Fe掺杂能增加催化剂表面吸附氧浓度和高价离子(Co^4+),这对提高催化氧化能力至关重要。采用颗粒物捕集器(DPF)作为载体涂覆CeO2涂层用于负载La0.9Sr0.1Co0.7Fe0.3O3催化剂进行柴油机台架实验,结果表明该催化剂具有较好的同时去除NOx和soot催化活性,最大NO转化率为23.0%,Tm为341.0℃,表明Fe掺杂对提高催化活性至关重要。The nano-perovskite catalyst La0.9Sr0.1Co1-xFexO3 was prepared by citric acid-EDTA complex method.The catalysts exhibit excellent catalytic activities for the simultaneous removal of NO and soot.Among them,the La0.9Sr0.1Co0.7Fe0.3O3 exhibits the best catalytic activity and wide activity window.The maximum NO conversion is32.5%at 380.0℃,and the maximum soot combustion rate(Tm)is 368.5℃.The results of H2-TPR and NO-TPD indicate that the Fe-doping can significantly improve the reduction performance at the low temperature,surface oxygen species activity and NO adsorption performance of catalyst,leading to the enhancement of the catalytic activity.The XPS results show a strong interaction between Co and Fe.With increasing of Fe-doping,the surface adsorbed oxygen concentration and(Co^4+)content could increase on the surface catalyst,it is essential to improve the catalytic oxidation ability.Based on the previous works,the commercial DPF carrier is used to coating the CeO2 coat,and the La0.9Sr0.1Co0.7Fe0.3O3 catalyst is further loaded to carry out the actual diesel engine bench test.The results show that the catalyst has good catalytic activity for simultaneous removal of NOx and soot.The best NO conversion can reach 23.0%,and the Tm was 341.0℃,indicating that the Fe-doping in the nano-perovskite catalysts can effectively improve the catalytic activity.It is expected that this study will provide strong theoretical support for the design and development of future four-way exhaust catalysts.

关 键 词：催化 多相反应 FE掺杂 氧化 NO 碳烟 台架实验 

分 类 号：TQ132.33[化学工程—无机化工] TQ138.11