文献类型：期刊文献

英文题名：SiO2 Deposition to Regulate Surface Barriers and Its Impact on ZSM-5 Catalyzed Reactions with Distinct Molecular Sizes

作者：Chen, Jiaxuan[1];Hu, Shen[1];Chen, Zhuo[1];Sun, Xincheng[1];Chen, Minhao[1];Chen, Tianjiao[1];Ye, Guanghua[1];Zhou, Xinggui[1]

机构：[1]East China Univ Sci & Technol, Sch Chem Engn, State Key Lab Chem Engn, Shanghai 200237, Peoples R China

年份：2023

卷号：153

期号：8

起止页码：2504

外文期刊名：CATALYSIS LETTERS

收录：;EI(收录号：20223812769266);WOS:【SCI-EXPANDED(收录号:WOS:000853300400001)】；

基金：This work was financially supported by the Shanghai RisingStar Program (21QA1402000), the National Natural Science Foundation of China (22078090), the Natural Science Foundation of Shanghai (21ZR1418100), and the Open Project of State Key Laboratory of Chemical Engineering (SKL-ChE-21C02).

语种：英文

外文关键词：Surface barriers; Zeolite catalysis; SiO2 deposition; ZSM-5; Molecular size

摘要：The effects of molecular size on SiO2 deposition regulated surface barriers and zeolite catalysis are probed, taking n-pentane isomerization and benzene alkylation with ethylene as model reactions. Chemical liquid deposition of SiO2 on the parent ZSM-5 sample only modifies its external surface slightly and passivates a small proportion of Bronsted acid sites. The apparent diffusivities increase significantly at 363-393K after SiO2 deposition, indicating SiO2 on ZSM-5 crystals reduces surface barriers at low temperatures. The conversion for n-pentane isomerization increases by up to 26% after SiO2 deposition, while the conversion for benzene alkylation decreases by up to 19%. Obviously, the positive effect of SiO2 deposition can be balanced out by the pore confinement effect at high temperatures, which is stronger for a larger molecule. This work provides a unique understanding of molecular size effects on surface barriers, which should serve to guide the design of zeolite catalysts. [GRAPHICS] .