文献类型：会议论文

英文题名：Size effects of Pt-Re bimetallic catalysts for glycerol hydrogenolysis

作者：Deng, Chenghao[1];Duan, Xuezhi[1];Zhou, Jinghong[1];Chen, De[2];Zhou, Xinggui[1];Yuan, Weikang[1]

机构：[1]E China Univ Sci & Technol, State Key Lab Chem Engn, Shanghai 200237, Peoples R China;[2]Norwegian Univ Sci & Technol, Dept Chem Engn, N-7491 Trondheim, Norway

会议论文集：2nd International Congress on Catalysis for Biorefineries (CatBior)

会议日期：SEP 22-25, 2013

会议地点：Dalian, PEOPLES R CHINA

语种：英文

外文关键词：Glycerol hydrogenolysis; Pt-Re; Size effect; CNTs; Coking

摘要：A series of Pt-Re/CNTs catalysts with different particle sizes have been synthesized and applied in glycerol hydrogenolysis to elucidate the size effects. The trend of turnover frequency (TOF) for these different sized Pt-Re/CNTs catalysts follows a volcanic curve, in which the TOF for Pt-Re/CNTs catalyst with particle size of 1.9 nm is ca. 7.5 times higher than that of 4.9 nm. X-ray photoelectron spectroscopy analysis revealed that the surface Pt/Re ratio decreased with the decrease of particle size. The enrichment of surface rhenium species on smaller particles probably led to the increase in the surface acidity, which could be one reason for the enhanced activity over smaller sized Pt-Ref/CNTs catalysts. However, too small sized Pt-Re/CNTs catalyst (e.g., 1.5 nm) suffered from severe coking, resulting in the lower activity. Moreover, the hydrogenolysis of different substrates (glycerol, 1,2-propanediol and 1,3-propanediol) over different sized Pt-Re/CNTs catalysts was also investigated. It was revealed that the reactivity declined in the following order: glycerol > 1,3-propanediol > 1,2-propanediol, and the cleavage of secondary C-O bond was favored over larger sized Pt-Ref CNTs catalyst. Based on these results, a possible reaction pathway depending on Pt-Re particle size was proposed. (C) 2014 Elsevier B.V. All rights reserved.