文献类型：期刊文献

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] State Key Laboratory of Chemical Engineering, East China University of Science and Technology, Shanghai 200237, China; [2] Department of Chemical Engineering, Norwegian University of Science and Technology, Trondheim 7491, Norway

年份：2014

卷号：234

起止页码：208

外文期刊名：Catalysis Today

收录：EI(收录号：20142617856532)

语种：英文

外文关键词：Hydrogenolysis - Hydrolysis - Catalyst activity - Binary alloys - Glycerol - X ray photoelectron spectroscopy - Particle size analysis

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-Re/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-Re/CNTs catalyst. Based on these results, a possible reaction pathway depending on Pt-Re particle size was proposed. ? 2014 Elsevier B.V.