文献类型：期刊文献

英文题名：Density Functional Theory for Adsorption of Gas Mixtures in Metal-Organic Frameworks

作者：Liu, Yu[1,2,3];Liu, Honglai[1,2];Hu, Ying[1,2];Jiang, Jianwen[3]

机构：[1]E China Univ Sci & Technol, State Key Lab Chem Engn, Shanghai 200237, Peoples R China;[2]E China Univ Sci & Technol, Dept Chem, Shanghai 200237, Peoples R China;[3]Natl Univ Singapore, Dept Chem & Biomol Engn, Singapore 117576, Singapore

年份：2010

卷号：114

期号：8

起止页码：2820

外文期刊名：JOURNAL OF PHYSICAL CHEMISTRY B

收录：;EI(收录号：20101012761963);WOS:【SCI-EXPANDED(收录号:WOS:000274842600033)】；

基金：This work was supported by the National University of Singapore (R279-000-198-112/133 and R279-000-243-123), the Singapore National Research Foundation oN the Competitive Research Programme (R279-000-261-281), the National Natural Science Foundation of China (No. 20736002), the National High Technology Research and Development Program of China (No. 2008AA062302), the Program for Changjiang Scholars and Innovative Research Team in University of China (No. IRT0721), and the 111 Project of China (No. B08021).

语种：英文

外文关键词：Equations of state - Gas mixtures - Monte Carlo methods - Gas adsorption - Organometallics - Crystalline materials - Density functional theory - Free energy - Intelligent systems

摘要：In this work, a recently developed density functional theory in three-dimensional space was extended to the adsorption of gas mixtures. Weighted density approximations to the excess free energy with different weighting functions were adopted for both repulsive and attractive contributions. An equation of state for hard-sphere Mixtures and a modified Benedict-Webb-Rubin equation for Lennard-Jones Mixtures were used to estimate the excess free energy of a uniform fluid. The theory was applied to the adsorption of CO2/CH4 and CO2/N-2 mixtures in two metal-organic frameworks: ZIF-8 and Zn-2(BDC)(2)(ted). To validate the theoretical predictions, grand canonical Monte Carlo simulations were also conducted. The predicted adsorption and selectivity from DFT were found to agree well with the simulation results. CO2 has stronger adsorption than CH4 and N-2, particularly in Zn-2(BDC)(2)(ted). The selectivity of CO2 over CH4 or N-2 increases with increasing pressure as attributed to the cooperative interactions of adsorbed CO2 molecules, The composition of the gas mixture exhibits a significant effect oil adsorption but not oil selectivity.