Template-induced Al distribution in MOR and enhanced activity in dimethyl ether carbonylation

Ying Li, Man Yu, Kai Cai, Meiyan Wang, Jing Lv, Russell F Howe, Shouying Huang, Xinbin Ma

Research output: Contribution to journalArticle

Abstract

As the activity of dimethyl ether (DME) carbonylation over mordenite proportionally correlates with the Brønsted acid sites (BAS) in 8-membered ring (8-MR), enhancing the concentration of BAS in the 8-MR of MOR is important to improve the efficiency of the reaction. Herein, we report that the distribution of the BAS in the zeolite catalyst H-MOR can be altered by the synthesis of H-MOR with different cyclic amine structure-directing templates, several of which have not been reported previously for MOR synthesis. By combining FTIR, ICP, TG analysis and DFT calculations, it is verified that the strength of the interaction between amine or sodium cations and [AlO4]- in the zeolite framework plays a decisive role in Al distribution, owing to the competitive effect between Na+ and the cyclic amine compensating negative charges from the framework [AlO4]-. Quantitative analysis of the BAS in the 12-MR and 8-MR identifies the optimum template for maximizing the BAS in the 8-MR. It is shown that the enhanced activity of the H-MOR for the DME carbonylation to methyl acetate correlates with the increase in the BAS in the 8-MR. Our finding thus provides a facile strategy to direct Al location within different channels of the zeolite, which must benefit spatially confined reaction systems.

Original languageEnglish
Pages (from-to)11374-11381
Number of pages8
JournalPhysical Chemistry Chemical Physics
Volume22
Issue number20
Early online date29 Apr 2020
DOIs
Publication statusPublished - 28 May 2020

Keywords

  • METHYL ACETATE
  • H-MORDENITE
  • ZEOLITE
  • IMPACT
  • DISPROPORTIONATION
  • MECHANISM
  • CHANNELS
  • ETHANOL
  • XYLENE

Fingerprint Dive into the research topics of 'Template-induced Al distribution in MOR and enhanced activity in dimethyl ether carbonylation'. Together they form a unique fingerprint.

  • Cite this