文献类型：期刊文献

英文题名：Optimizing spatial pore-size and porosity distributions of adsorbents for enhanced adsorption and desorption performance

作者：Ye, Guanghua[1,2];Duan, Xuezhi[1];Zhu, Kake[1];Zhou, Xinggui[1];Coppens, Marc-Olivier[2];Yuan, Weikang[1]

机构：[1]E China Inst Theoret Phys, State Key Lab Chem Engn, Shanghai 200237, Peoples R China;[2]UCL, Dept Chem Engn, London WC1E 7JE, England

年份：2015

卷号：132

起止页码：108

外文期刊名：CHEMICAL ENGINEERING SCIENCE

收录：;EI(收录号：20151900827069);WOS:【SCI-EXPANDED(收录号:WOS:000355132500011)】；

基金：X.G. is supported by the National Basic Research Program of China (2012CB720501), and by the National Natural Science Foundation of China (21376076), G.Y. is supported by the China Scholarship Council (CSC) for the research at UCL, and M.-O.C. is supported by the UK's EPSRC "Frontier Engineering" Centre for Nature Inspired Engineering.

语种：英文

外文关键词：Spatial distributions; Adsorbent design; Mass transfer; Continuum approach; Adsorption/desorption performance; Optimal porosity

摘要：This paper shows that a uniform spatial distribution in meso/macroporosity of adsorbents maximizes their adsorption and desorption performance. It highlights the importance of optimizing porosity and pore diameter, not only at the nanoscale but also at larger length scales. The effects of spatial pore size and porosity distributions on mass transfer in adsorbents are studied by using a continuum approach. These effects are evaluated by comparing the adsorption/desorption performance of adsorbents subjected to a square wave concentration perturbation with a wide range of cycle period (10-100,000 s) for the adsorption of n-pentane on 5A zeolite adsorbents. The uniformly distributed pore size and porosity is the preferred structure, which is confirmed by using four empirical tortuosity-porosity relations. Further optimization of the uniform structure shows that its optimal average porosity is in the range of 04-0.6 when the perturbation cycle period is between 100 s and 2000 s and the volume-averaged pore diameter is between 10 nm and 150 nm. The relationships between optimal average porosity, cycle period and volume-averaged pore diameter are determined and explained. These results should serve to guide the synthesis of adsorbents. (C) 2015 Elsevier Ltd. All rights reserved,