Customizing Metal‐Organic Frameworks by Lego‐Brick Strategy for One‐Step Purification of Ethylene from a Quaternary Gas Mixture
Haoran Sun, Fuqiang Chen, Rundao Chen, Jiaqi Li, Lidong Guo, Ying Liu, Fuxing Shen, Qiwei Yang, Zhiguo Zhang, Qilong Ren, Zongbi Bao
Abstract
Abstract One‐step purification of ethylene (C 2 H 4 ) from a quaternary gas mixture of C 2 H 6 /C 2 H 4 /C 2 H 2 /CO 2 by adsorption is a promising separation process, yet developing adsorbents that synergistically capture various gas impurities remains challenging. Herein, a Lego‐brick strategy is proposed to customize pore chemistry in a unified framework material. The ethane‐selective MOF platform is further modified with customized binding sites to specifically adsorb acetylene and carbon dioxide, thus one‐step purification of C 2 H 4 with high productivity of polymer‐grade product (134 mol kg −1 ) is achieved on the assembly of porous coordination polymer‐2,5‐furandicarboxylic acid (PCP‐FDCA) and PCP‐5‐aminoisophthalic acid (IPA‐NH 2 ). Computational studies verify that the low‐polarity surface of this MOFs‐based platform provides a delicate environment for C 2 H 6 recognition, and the specific binding sites (FDCA and IPA‐NH 2 ) exhibit favorable trapping of C 2 H 2 and CO 2 via CH δ+ ···O δ− and C δ+ ···N δ− electrostatic interactions, respectively. The proposed Lego‐brick strategy to customize binding sites within the MOFs structure provides new ideas for the design of adsorbents for compounded separation tasks.