Three‐in‐One C<sub>2</sub>H<sub>2</sub>‐Selectivity‐Guided Adsorptive Separation across an Isoreticular Family of Cationic Square‐Lattice MOFs
Subhajit Dutta, Soumya Mukherjee, Omid T. Qazvini, Arvind Kumar Gupta, Shivani Sharma, Debanjan Mahato, Ravichandar Babarao, Sujit K. Ghosh
Abstract
Abstract Energy‐efficient selective physisorption driven C 2 H 2 separation from industrial C2‐C1 impurities such as C 2 H 4 , CO 2 and CH 4 is of great importance in the purification of downstream commodity chemicals. We address this challenge employing a series of isoreticular cationic metal‐organic frameworks, namely iMOF‐nC ( n =5, 6, 7). All three square lattice topology MOFs registered higher C 2 H 2 uptakes versus the competing C2‐C1 gases (C 2 H 4 , CO 2 and CH 4 ). Dynamic column breakthrough experiments on the best‐performing iMOF‐6C revealed the first three‐in‐one C 2 H 2 adsorption selectivity guided separation of C 2 H 2 from 1:1 C 2 H 2 /CO 2 , C 2 H 2 /C 2 H 4 and C 2 H 2 /CH 4 mixtures. Density functional theory calculations critically examined the C 2 H 2 selective interactions in iMOF‐6C. Thanks to the abundance of square lattice topology MOFs, this study introduces a crystal engineering blueprint for designing C 2 H 2 ‐selective layered metal‐organic physisorbents, previously unreported in cationic frameworks.