能源化学(英文版)

能源化学(英文) ›› 2005, Vol. 14 ›› Issue (2): 119-124.

• Articles • 上一篇    

Theoretical Study of Ethanethiol Adsorption on HZSM-5 Zeolite

Renqing Lv, Guangmin Qiu, Chenguang Liu   

  1. 1. College of Chemistry and Chemical Engineering, China University of Petroleum, Dongying 257061, China; 2. College of Petroleum Engineering, China University of Petroleum, Dongying 257061, China
  • 出版日期:2005-06-30 发布日期:2005-06-30

Theoretical Study of Ethanethiol Adsorption on HZSM-5 Zeolite

Renqing Lv, Guangmin Qiu, Chenguang Liu   

  • Online:2005-06-30 Published:2005-06-30

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摘要： The density functional theory and the cluster model methods have been employed to investigate the interactions between ethanethiol and HZSM-5 zeolites. Molecular complexes formed by the adsorption of ethanethiol on silanol H3SiOH with two coordination forms, model Bronsted acid sites of zeolite cluster H3Si(OH)Al(OH)2SiH3 interaction with ethanethiol, aluminum species adsorbed ethanethiol 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 6-31G(d) basis set level for silicon, aluminum, oxygen, carbon, and sulfur atoms. The structures and energy changes of different coordination forms of H3Si(OH)Al(OH)2SiH3-ethanethiol, silanol-ethanethiol and Al(OH)3-ethanethiol have been studied. The calculated results showed the nature of interactions was van der Waals force as exhibited by not much change in geometric structures and properties. The preference order of ethanethiol adsorbed on HZSM-5 zeolite may be residual aluminum species, bridging hydroxyl groups and silanol OH groups from the adsorption heat. The adsorbed models of protonized ethanethiol on bridging hydroxyl OH groups and linear hydrogen bonded ethanethiol on bridging OH groups suggested in literature might not exist as revealed by this theoretical calculation. Possible adsorption models were obtained for the first time.

关键词: density functional theory, ethanethiol, ZSM-5 zeolite, model cluster

Abstract: The density functional theory and the cluster model methods have been employed to investigate the interactions between ethanethiol and HZSM-5 zeolites. Molecular complexes formed by the adsorption of ethanethiol on silanol H3SiOH with two coordination forms, model Bronsted acid sites of zeolite cluster H3Si(OH)Al(OH)2SiH3 interaction with ethanethiol, aluminum species adsorbed ethanethiol 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 6-31G(d) basis set level for silicon, aluminum, oxygen, carbon, and sulfur atoms. The structures and energy changes of different coordination forms of H3Si(OH)Al(OH)2SiH3-ethanethiol, silanol-ethanethiol and Al(OH)3-ethanethiol have been studied. The calculated results showed the nature of interactions was van der Waals force as exhibited by not much change in geometric structures and properties. The preference order of ethanethiol adsorbed on HZSM-5 zeolite may be residual aluminum species, bridging hydroxyl groups and silanol OH groups from the adsorption heat. The adsorbed models of protonized ethanethiol on bridging hydroxyl OH groups and linear hydrogen bonded ethanethiol on bridging OH groups suggested in literature might not exist as revealed by this theoretical calculation. Possible adsorption models were obtained for the first time.

Key words: density functional theory, ethanethiol, ZSM-5 zeolite, model cluster