The modulation of ethane-selective adsorption performance in series of bimetal PCN-250 metal-organic frameworks: Impact of metal composition
The modulation of ethane-selective adsorption performance in series of bimetal PCN-250 metal-organic frameworks: Impact of metal composition
复制标题
双金属 PCN-250 金属有机骨架系列中乙烷选择性吸附性能的调节：金属成分的影响
DOI：
10.1002/aic.17385
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发表时间：
2022
期刊：
影响因子：
3.7
通讯作者：
Xia Qibin
中科院分区：
文献类型：
--
作者：
Wu Houxiao;Chen Yongwei;Yuan Yinuo;Lv Daofei;Tu Shi;Liu Zewei;Li Zhong;Xia Qibin
高性能吸附剂的开发在乙烷/乙烯（C2 H6/C2 H4）混合物的分离中引起了越来越多的关注。在本工作中，合成了一系列超稳定的C2 H6-选择性金属有机框架（MOFs），PCN-250及其替代形式PCN-250（Fe 2 M2+，M2+= Ni 2+，Co 2+，Zn 2+，Mn 2+），以研究金属组成对C2 H6-选择性性能的影响。在298 K和100 kPa下，PCN-250（Fe 2Co）表现出最大的C2 H6吸收（6.21 mmol/g），而PCN-250（Fe 2 Zn）表现出最高的C2 H6/C2 H4理想吸附溶液理论（IAST）选择性（1.70）。分子模拟结果表明，金属离子的引入对骨架中原子的部分电荷有不同的影响，从而改变了骨架对C2 H6/C2 H4分子的吸附亲和力.此外，对PCN-250（Fe 2 Zn）的研究表明，金属中心的正部分电荷的增加以及来自有机配体的苯环（BR）中心的电荷密度的降低将有利于提高所需的C2 H6选择性。
The developments of high‐performance adsorbents have attracted ever‐increasing attention in the separation of ethane/ethylene (C2H6/C2H4) mixtures. In this work, a series of ultra‐stable C2H6‐selective metal–organic frameworks (MOFs), PCN‐250, and its bimetal version PCN‐250(Fe2M2+, M2+= Ni2+, Co2+, Zn2+, Mn2+), were synthesized to investigate the influence of metal compositions on the C2H6‐selective performance. Among the five materials, at 298 K and 100 kPa, PCN‐250(Fe2Co) showed the largest C2H6uptake (6.21 mmol/g) while PCN‐250(Fe2Zn) exhibited the highest C2H6/C2H4ideal adsorption solution theory (IAST) selectivity (1.70). The molecular simulation revealed that the introduced metal ions have different influences on the atomic partial charge within the framework which varied the framework adsorption affinities toward C2H6/C2H4molecules. Moreover, the research on PCN‐250(Fe2Zn) suggested that the increased positive partial charge of metal sites together with a decreased charge density of benzene ring (BR) sites from the organic ligands will be beneficial to improve the desired C2H6selectivity.