文献类型：期刊文献

英文题名：Computational evaluation of RHO-ZIFs for CO2 capture: From adsorption mechanism to swing adsorption separation

作者：Gao, Weiqun[1];Wang, Shuangfu[1];Zheng, Weizhong[1];Sun, Weizhen[1];Zhao, Ling[1]

机构：[1]East China Univ Sci & Technol, Sch Chem Engn, State Key Lab Chem Engn, Shanghai 200237, Peoples R China

年份：2023

卷号：313

外文期刊名：SEPARATION AND PURIFICATION TECHNOLOGY

收录：;EI(收录号：20231013677096);WOS:【SCI-EXPANDED(收录号:WOS:000949828600001)】；

基金：Grant numbers: Major Science and Technology Special Project of XinjiangAutonomous Region (2022A01006-1) .

语种：英文

外文关键词：Zeolitic imidazolate framework; CO 2 capture; Monte Carlo; Density functional theory; Swing adsorption processes

摘要：RHO zeolitic imidazolate frameworks (ZIF) are promising materials regarding chemical stabilities and CO2 capture capacities. However, their CO2 adsorption, separation properties, and applications in swinging adsorp-tion processes have not been systematically investigated. Therefore, molecular simulations were conducted for CO2 adsorption and separation from natural gas and flue gas on three representative RHO-ZIFs (ZIF-71, ZIF-96, and ZIF-97). After identifying the most reasonable forcefield parameters for the considered gases and ZIFs (<10 % deviation), the CO2 adsorption capacities under various operating conditions were predicted. ZIF-96 was calculated to possess comparable CO2 uptake (3.42 mol/kg) with the record ZIF-69 (3.23 mol/kg) at 1 bar and 273 K due to the functionalized -CN and -NH2 groups. Despite containing the polar -CH3OH groups, ZIF-97 showed a similar saturated CO2 adsorption as ZIF-71, which contains less-polar dichloro-imidazolate groups. Analysis reveals that the specific position of -OH in ZIF-97 makes the 4-apertures more attractive to CO2 than the 6-or 8-apertures. Such narrow preferential adsorption sites limit CO2 occupancy. In addition, ZIF-96 has great CO2/CH4 and CO2/N2 selectivities over a wide range of temperatures, pressures, and CO2 concentrations, outperforming many well-known MOFs. Based on several specific separation metrics, capturing CO2 using ZIF-96 in the PTSA process is considered the most appropriate approach for natural gas purification and fuel gas treatment.