The carbonylation of synthetic gas to ethanol by dimethyl ether has attracted much attention because of its high atomic economy and environmental friendliness.The carbonylation of dimethyl ether to methyl acetate is the core reaction of this route.In the development of carbonylation molecular sieve catalysts, the directional regulation of acidity is the focus and difficulty.

In recent years, the research team led by Prof. ZHUwenliang and Prof. LIU zhongmin has been committed to the basic research and industrial application development of dimethyl ether carbonylation to methyl acetate.In 2017, the research team and Shaanxi Yanchang Petroleum Group built the world's first 100,000-ton/year industrial demonstration device for ethanol production from coal via dimethyl ether, and achieved smooth production and stable operation.At the same time, a series of progress has been made in the application of basic research, such as the study of the reaction mechanism of dimethyl ether carbonylation(J Mol Catal A-Chem, 2016, 417:1), the in-situ synthesis and regulation of zeolite for dimethyl ether carbonylation performance(Catal Sci Technol, 2015, 5, 1961), and the recognition and regulation of acid sites of carbonylationzeolite(Catal Sci Technol，2020, 10, 4663;Catal Commun,2020 147 106161). The development of industrial catalysts for the carbonylation of dimethyl ether to methyl acetate provides theoretical support.

Recently, the research team has made new progress in regulating the properties of mordenite by post-treatment. The results show that the acidic properties of MOR can be further optimized by hydrothermal treatment of tetraethyl ammonium hydroxide, thereby preparing a zeolite catalyst for dimethyl ether carbonylation with excellent performance.

It was found that changing the post-treatment conditions (solution concentration and temperature) could regulate the distribution of Brongted acid center in different channels of the MOR without affecting its crystal morphology and pore structure，and the change of post-treatment temperature had a great influence on the acidity of MOR. The sample obtained at 160℃increases the conversion rate of dimethyl ether from 22% (for parent sample )to 98%, the space-time yield of methyl acetate reached 3.8 mmol/g/h, which was nearly 5 times that of the parent sample ( 0.8 mmol/g/h). This work provides an effective strategy for the design and preparation of high-performance dimethyl ether carbonylation catalysts.

Related research results, entitled "Regulation of HMOR properties and its effect on DME carbonylation by post-treatment ", were recently accepted onApplied Chemical Industry. This research was supported by the National Natural Science Foundation of China and the “Transformational Technologies for Clean Energy and Demonstration”, Strategic Priority Research Program of the Chinese Academy of Sciences.(Text by DINGxingnong ZHU wenliang)