中国科学院大连化物所黄延强团队报道了复合ZnZrO沸石催化剂上串联CO₂加氢和甲苯甲基化合成二甲苯。相关研究成果发表在2023年7月28日出版的《德国应用化学》。

从CO2加氢中选择性合成特定的增值芳烃对于缓解CO₂排放引起的能源和气候问题至关重要。

该文报道了一种高活性的ZnZrO和HZSM-5的复合催化剂（ZZO/Z5-SG），用于在甲苯存在下通过偶联反应以CO₂加氢合成二甲苯，实现了86.5%的二甲苯选择性和10.5%的CO₂转化率。二甲苯的时空产率可达到215mg gcat^-1h^-1，超过了大多数报道的CO₂加氢催化剂。ZZO/Z5-SG性能的提高可能是由于ZZO组分对CO₂吸附的高分散性和丰富的氧空位，由于两组分之间的密切相互作用，氢活化和转移更可行，以及甲酸酯中间体的稳定性增强。引入甲苯对甲酸酯深度加氢过程中甲氧基和甲醇的消耗也推动了CO₂的定向转化。

附：英文原文

Title: Xylene Synthesis Through Tandem CO2 Hydrogenation and Toluene Methylation Over a Composite ZnZrO Zeolite Catalyst

Author: Xin Shang, Hongying Zhuo, Qiao Han, Xiaofeng Yang, Guangjin Hou, Guodong Liu, Xiong Su, Yanqiang Huang, Tao Zhang

Issue&Volume: 2023-07-28

Abstract: Selective synthesis of specific value-added aromatics from CO2 hydrogenation is of paramount interest for mitigating energy and climate problems caused by CO2 emission. Herein, we report a highly active composite catalyst of ZnZrO and HZSM-5 (ZZO/Z5-SG) for xylene synthesis from CO2 hydrogenation via coupling reaction in the presence of toluene, achieving a xylene selectivity of 86.5% with CO2 conversion of 10.5%. A remarkably high space time yield of xylene could reach 215 mg gcat-1 h-1, transcending most reported catalysts for CO2 hydrogenation. The enhanced performance of ZZO/Z5-SG could be owing to high dispersion and abundant oxygen vacancies of ZZO component for CO2 adsorption, more feasible hydrogen activation and transfer due to the close interaction between two components, and enhanced stability of the formate intermediate. The consumption of methoxy and methanol from the deep hydrogenation of formate by introduced toluene also propels an oriented conversion of CO2.

DOI: 10.1002/anie.202309377

Source: https://onlinelibrary.wiley.com/doi/10.1002/anie.202309377