化工进展 ›› 2022, Vol. 41 ›› Issue (3): 1115-1120.doi: 10.16085/j.issn.1000-6613.2021-2239

• 观点 • 上一篇    下一篇

CO2加氢一步制二甲醚展望

刘畅(), 刘忠文()   

  1. 陕西师范大学化学化工学院,陕西省合成气转化重点实验室,陕西 西安 710119
  • 收稿日期:2021-11-01 修回日期:2021-11-26 出版日期:2022-03-23 发布日期:2022-03-28
  • 通讯作者: 刘忠文 E-mail:chang_liu@snnu.edu.cn;zwliu@snnu.edu.cn
  • 作者简介:刘畅(1987—),男,副研究员,研究方向为CO2加氢与合成气转化。E-mail:chang_liu@snnu.edu.cn
  • 基金资助:
    国家自然科学基金(21636006);中央高校优秀成果培育计划(GK201901001);陕西省自然科学基础研究计划青年项目(2021JQ-306)

Perspective on the one-step CO2 hydrogenation to dimethyl ether

LIU Chang(), LIU Zhongwen()   

  1. Key Laboratory of Syngas Conversion of Shaanxi Province, School of Chemistry and Chemical Engineering, Shaanxi Normal University, Xi’an 710119, Shaanxi, China
  • Received:2021-11-01 Revised:2021-11-26 Online:2022-03-23 Published:2022-03-28
  • Contact: LIU Zhongwen E-mail:chang_liu@snnu.edu.cn;zwliu@snnu.edu.cn

摘要:

CO2加氢制二甲醚(DME)是有潜力实现CO2资源化利用的重要途径之一。与光、电催化相比,CO2的非均相催化转化具有转化效率高等优点,但目前CO2加氢一步制备DME催化剂的反应活性较低、稳定性较差。本文在简要介绍CO2加氢一步制DME的铜基双功能催化剂、复合氧化物和氮化镓催化剂的基础上,重点总结了活性中心结构和反应机理的研究进展。对于铜基双功能催化剂,CO2加氢经甲醇中间体合成DME,其中还原态铜(Cu0、Cu+及Cu δ+,0<δ<2)是其催化活性中心,且还原态铜的分散度及稳定性、固体酸的性质和酸性位分布以及两类活性中心的耦合效应是决定DME收率和催化剂稳定性的关键因素。与此相反,DME是氮化镓催化CO2加氢的初级产物。这与铜基双功能催化剂有着本质区别,属新催化剂体系。在此基础上,文章对CO2加氢制DME的可能研究方向进行了展望,认为“二甲醚经济”更具发展潜力。

关键词: 二氧化碳加氢, 二甲醚, 氮化镓, 铜, 双功能催化剂

Abstract:

The hydrogenation of CO2 to dimethyl ether (DME) is a potential method for the efficient utilization of CO2 as a renewable resource. In comparison with the photocatalytic and electrocatalytic routes, the thermal conversion of CO2 over a solid catalyst exhibits a higher efficiency. However, the reported catalysts for the one-step hydrogenation of CO2 to DME commonly suffer from a lower activity and a poorer stability. In this perspective, progresses on the structure of active sites and the reaction mechanism of the one-step hydrogenation of CO2 to DME are summarized for the Cu-based bifunctional catalyst and the recently reported GaN catalyst. In the case of the Cu-based bifunctional catalyst, DME is formed via the CO2 hydrogenation to methanol and the dehydration of the intermediate methanol to DME. Moreover, copper at reduced state (Cu0, Cu+ or Cu δ+, 0<δ<2) is the active site for the CO2 hydrogenation, and the DME yield and the stability of the bifunctional catalyst are mainly determined by the dispersion and the stability of reduced Cu, the strength and distribution of acid sites, and the synergetic effect between reduced Cu and the acid sites. In contrast, the GaN catalyzed DME synthesis proceeds via the direct hydrogenation of CO2 to the primary product of DME, which is totally different from that over the Cu-based bifunctional catalysts. Based on these analyses, the challenges and the further researches on the one-step hydrogenation of CO2 to DME are provided, and the benefit of the DME economy is remarked.

Key words: CO2 hydrogenation, dimethyl ether, gallium nitride, copper, bifunctional catalyst

中图分类号: 

  • O643.32