摘要
采用离子交换法制备Fe-Beta分子筛,重点研究不同硅铝比对Fe-Beta的低温性能影响。以NO、NH3、H2O、CO2为反应物的小样催化性能评价显示,当硅铝比为30时,Fe-Beta分子筛催化剂展现出优异的催化活性。研究表明,自主制备的Fe-Beta可有效降低NOx排放,副产物生成量极低。采用X射线衍射、扫描电镜、氮气吸附、氨气程序升温脱附、固体紫外光谱等手段研究分子筛物相结构与分子筛催化剂活性之间关系。结果表明,当控制Beta硅铝比为30,Fe负载量为1.3%时,Fe-Beta具有适宜的比表面积、酸性位及优异的NH3-SCR活性。UV-vis谱图显示,分子筛中存在不同的Fe物种,通过分峰计算发现,孤立的Fe^3+、低聚物、高聚物大颗粒3种同时存在,其中孤立的Fe^3+、低聚的Fex^3+Oy为Fe-beta的SCR活性位点。高性能Fe-Beta催化剂的制备对指导满足非道路四阶段排放法规的高效环保SCR催化剂开发具有重要的理论及实践意义。
Fe-Beta molecular sieves were prepared by ion exchange method.The effects of different silicon to alumina ratios on the Fe-Beta NH3-SCR performance were studied.The synthetic gas bench results showed that when the SAR=30,Fe-Beta had excellent low temperature activity.The Fe-Beta could effectively control the NOx emission with a supper low N2O emission.X-ray diffraction,scanning electron microscopy,nitrogen adsorption,ammonia temperature programmed desorption,and UV-vis spectrometer were used to study the relationship between phase structure and its NH3-SCR activity.The results showed that Fe-Beta with the SAR of 30 and iron loading of 1.3%had a suitable specific surface area and acidity,and excellent NH3-SCR activity.Fe species were composed of isolated Fe^3+,oligomers,and high polymer large particles.The isolated Fe^3+and oligomers were the active sites of Fe-beta.The preparation of active Fe-Beta catalysts had important theoretical and practical significance for guiding the development of efficient and environmental friendly SCR catalysts that meet the requirements of China IV off-road regulations.
作者
马江丽
杨冬霞
于飞
赖慧龙
冯丰
常仕英
MA Jiangli;YANG Dongxia;YU Fei;LAI Huilong;Feng Feng;CHANG Shiying(State-Local Joint Engineer Laboratory of Precious Metals Catalytic Technology andApplication,Kunming Sino-platinum Metals Catalysts Co.,Ltd.,Kunming 650106,China;State Key Laboratory of Advanced Technologies for Comprehensive Utilization ofPlatinum Metals,Kunming Institute of Precious Metals,Kunming 650106,China;Faculty of Environmental Science and Engineering,Kunming University of Science and Technology,Kunming 650500,China)
出处
《功能材料》
EI
CAS
CSCD
北大核心
2020年第5期5202-5207,共6页
Journal of Functional Materials
基金
云南省科技厅重大科技专项计划资助项目(2018ZE001)。
