Effects of surface modification on coking, deactivation and para-selectivity of H-ZSM-5 zeolites during ethylbenzene disproportionation

文化大學機構典藏 CCUR > 理工學院 > 理學院 > 化學系所 > 期刊論文 > Item 987654321/2979

jsp.display-item.identifier=請使用永久網址來引用或連結此文件: https://irlib.pccu.edu.tw/handle/987654321/2979

题名:	Effects of surface modification on coking, deactivation and para-selectivity of H-ZSM-5 zeolites during ethylbenzene disproportionation
作者:	Chen WH Tsai TC Jong SJ Zhao Q Tsai CT Wang IK Lee HK Liu SB
贡献者:	化學系
关键词:	shape selectivity Si-CVD coking H-ZSM-5 zeolite NMR
日期:	2002
上传时间:	2009-12-11 09:36:41 (UTC+8)
摘要:	The effects of coking and surface modification of H-ZSM-5 zeolites on enhancement of para-diethylbenzene selectivity during disproportionation of ethylbenzene have been investigated. Surface modifications of the zeolites by silica chemical vapor deposition (Si-CVD) and by stepwise lepidine adsorption and/or Si-CVD treatments were examined. The acidity, sorption capacity, stability, and coke content of the samples were characterized by various techniques, such as adsorption, TGA, IR, Xe-129 NMR, and solid-state Al-27 and P-31 MAS NMR. The performance of the para-selective process was studied by the correlation between the observed para-selectivity and conversion. The working principle responsible for the para-selective feature was found due to the combined effects of diffusion limitations and inactivation of external active sites. At the extreme of low conversion, the feature depends mostly on the former effect, whereas the latter becomes progressively important with increasing conversion. At high conversion, while both effects are important, diffusion controlled limitations associated with steric hindrances near the pore mouths plays the predominant role, especially towards saturating surface SiO2 loading. (C) 2002 Elsevier Science B.V. All rights reserved.
關聯:	JOURNAL OF MOLECULAR CATALYSIS A-CHEMICAL Volume: 181 Issue: 1-2 Pages: 41-55
显示于类别:	[化學系所] 期刊論文

文件中的档案:

档案	描述	大小	格式	浏览次数
index.html		0Kb	Text	584	检视/开启

在CCUR中所有的数据项都受到原著作权保护.

数据加载中.....