HZSM-5沸石分子筛吸附H_2S的理论研究  

The Theoretical Study of H_2S Adsorption on HZSM - 5 Zeolite

作　　者：邱广敏[1] 黄宝丽[2] 王新民[3] 李祥同[3] 

机构地区：[1]石油大学(华东)石油工程学院 [2]石油大学(华东)仪表厂 [3]胜利油田有限公司

出　　处：《石油与天然气化工》2006年第2期107-109,共3页Chemical engineering of oil & gas

摘　　要：采用密度泛函理论和模型簇法研究了H2S和ZSM-5沸石分子筛的相互作用。对H2S吸附在硅羟基H2SiOH上可能的两种极限配位方式及吸附在沸石模型簇H2Si(OH)Al(OH)2SiH3桥羟基 B酸可能的两种极限配位方式进行了比较分析。所有模型簇采用B3LYP混合方法对氢原子在3-21G 基组水平上,对硅原子、铝原子、氧原子、硫原子在6-31G(d)基组水平上进行了全优化和频率分析。着重考察了H2S与硅羟基及分子筛模型簇不同配位方式所形成的配合物的结构和能量变化。计算结果表明,由于在形成H2S-沸石和H2S-硅羟基配合物的结构和性质变化不明显,它们之间的作用力为范德华作用力。从H2S在沸石分子筛的桥羟基和硅羟基与H2S相互作用的吸附热可以推断,H2S优先吸附在桥羟基上。The density functional theory and the cluster model method have been employed to investigate the interactions between H2S and HZSM -5 zeolites. Molecular complexes formed by the adsorption of H2 S on sil anol H3 Si ( OH ) with two coordination forms, and model Bronsted acid sites of zeolite cluster H3Si ( OH ) Al (OH)2SiH3 interaction with H2S have been comparatively studied. Full optimization and frequency analysis of all cluster models have been carried out using B3LYP hybrid method at 3 - 21G basis level for hydrogen atoms and 6 31C(d) basis set level for silicon, aluminum, oxygen, and sulfur atoms. The structures and energy changes of two different coordination forms between H2S and H3Si ( OH) Al( OH) 2SiH3 as well as two forms of H2S - silanol complexes have been comparatively studied. The calculated results showed that the nature of interactions lead to the formation of the zeolite cluster - H2S and silanol H2S complexes was van der Waals force confirmed by a little change of geometric structures and properties. H2S adsorbed on bridging hydroxyl group prior to silanol OH group from the adsorption heat.

关 键 词：密度泛函理论 H2S ZSM-5沸石分子筛 模型簇 

分 类 号：O647.31[理学—物理化学]