Ordered Mesoporous Carbon Supported Metal Nano Catalysts for Shape-Selective Catalysis
ZHU Xiaojuan, SUN Yafei, WANG Lili, WU Mengmeng, WAN Ying
Shanghai Frontiers Science Center of Biomimetic Catalysis, Shanghai Key Laboratory of Rare Earth Functional Materials, Key Laboratory of Resource Chemistry of Ministry of Education, Shanghai Non-Carbon Energy Conversion and Utilization Institute, Shanghai Normal University, Shanghai 200234, China
Abstract:Shape-selective catalysis plays an important role in fine chemical synthesis and other fields. Ordered mesoporous materials have relatively large pore diameters and regular pore structures, and it is of great significance to explore their shape-selectivity. Here, the effect of the pore size of the ordered mesoporous carbon confined AuPd alloy catalyst on the selective oxidation of benzyl alcohol compounds and the selective hydrogenation of quinoline compounds was studied. The results clearly showed the relationship between molecular size of substrate and mesopore size of catalyst. Small-sized substrate molecules such as benzyl alcohol and quinoline could diffuse into the mesoporous pores of 3.5 nm and oxidation/reduction on the surface of the alloy; while the inner diffusion of larger molecules such as 2-methylbenzyl alcohol, and 3,5-di-tert-butylbenzyl alcohol were seriously inhibited resulting in undetectable conversion. When the pore size increases, larger molecules could diffuse into mesopores and accessible to the metal sites. The turn-over frequency (TOFPd) of 2-methylbenzyl alcohol oxidation could reach 307 h-1 in the catalyst with 5.0 nm-pores and TOFPd for the oxidation of 3,5-di-tert-butylbenzyl alcohol is 140 h-1 in a 6.0 nm-pore mesoporous catalyst.
ZHU Xiaojuan,SUN Yafei,WANG Lili et al. Ordered Mesoporous Carbon Supported Metal Nano Catalysts for Shape-Selective Catalysis[J]. Chemical Reaction Engineering and Technology, 2022, 38(5): 420-430.