Enhancement of the dimethyl ether carbonylation activation via regulating acid sites distribution in FER zeolite framework

Yanxia Guo; Sen Wang; Rui Geng; Pengfei Wang; Shiying Li; Mei Dong; Zhangfeng Qin; Jianguo Wang; Weibin Fan

doi:10.1016/j.isci.2023.107748

Enhancement of the dimethyl ether carbonylation activation via regulating acid sites distribution in FER zeolite framework

iScience. 2023 Aug 28;26(10):107748. doi: 10.1016/j.isci.2023.107748. eCollection 2023 Oct 20.

Authors

Yanxia Guo^{1

2}, Sen Wang¹, Rui Geng^{1

2}, Pengfei Wang¹, Shiying Li¹, Mei Dong¹, Zhangfeng Qin¹, Jianguo Wang^{1

2}, Weibin Fan¹

Affiliations

¹ State Key Laboratory of Coal Conversion, Institute of Coal Chemistry, Chinese Academy of Sciences, Taiyuan, Shanxi 030001, China.
² University of Chinese Academy of Sciences, Beijing 100049, China.

Abstract

The carbonylation of dimethyl ether (DME) with CO is a key step for ethanol synthesis from syngas, but traditional mordenite (MOR) zeolite shows low catalytic stability. Herein, various FER zeolite nanosheets were prepared with four types of organic templates. The catalytic performance of FER in DME carbonylation is strongly dependent on the location of strong acid site in framework, which can be effectively regulated by altering organic template. FER-MORP sample synthesized with morpholine shows the highest DME conversion of 53%, thus, giving a methyl acetate space-time yield (STY_MA) of 0.889 mmol g^-1 h^-1. DFT calculation, NH₃-IR, ¹H/²⁷Al/²⁹Si MAS NMR, and in situ DRIFTS results indicate that morpholine directs more Al species, or strong Brønsted acid sites (BAS), to locate in 8-membered ring (8-MR) channels, which not only enhances carbonylation activity but also suppresses formation of coke species. The catalytic performance is well maintained within 4 repeated recycles (∼460 h).

Keywords: Energy materials; Interface science; Physical inorganic chemistry.