石油化工2018，Vol.47Issue(2)：115-119,5.DOI:10.3969/j.issn.1000-8144.2018.02.002
铼前体对乙烯环氧化银催化剂性能的影响
Effect of rhenium precursor on performance of silver catalyst for ethylene epoxidation
任冬梅 1李建伟 2李金兵 2代武军 1梁汝军1
作者信息
- 1. 中国石化 北化院燕山分院,北京 102500
- 2. 北京化工大学 化工资源有效利用国家重点实验室,北京 100029
- 折叠
摘要
Abstract
A series of supported silver catalysts for ethylene epoxidation were prepared by co-impregnation and secondary impregnation using the precursors of inorganic perrhenic acid(HReO4) and organic methyltrioxorhenium(CH3ReO3),respectively. The effects of heating temperature and rhenium loading method on the catalyst performance were investigated. The catalysts were characterized by TG-DSC,TEM,SEM,XPS and O2-TPD. The evaluation results show that the Re*/Ag-Cs catalyst with the precursor of CH3ReO3loaded first,and the silver and cesium loaded late after treatment at 120℃ has the best performance with the reaction temperature of 218.1 ℃ and ethylene oxide selectivity of 83.16%. The analysis results show that single rhenium component is distributed randomly on the α-Al2O3crystal,different rhenium precursors have no effect on the valence of silver and cesium in the catalyst. The average particle size of the silver particle is 110 nm for the Ag-Cs-Re catalyst,while it is 80 nm for the Re*/Ag-Cs catalyst. The desorption temperature of weakly adsorbed oxygen on the Re*/Ag-Cs catalyst is around 10 ℃ lower than that on the Ag-Cs-Re catalyst,which indicates higher activity of the Re*/Ag-Cs catalyst.关键词
铼前体/乙烯环氧化/银催化剂/高铼酸/甲基三氧化铼Key words
rhenium precursor/ethylene epoxidation/silver catalyst/perrhenic acid/methyltrioxorhenium分类
化学化工引用本文复制引用
任冬梅,李建伟,李金兵,代武军,梁汝军..铼前体对乙烯环氧化银催化剂性能的影响[J].石油化工,2018,47(2):115-119,5.
