Benchmark single-step ethylene purification from ternary mixtures by a customized fluorinated anion-embedded MOF.

Ethylene (C 2 H 4 ) purification from multi-component mixtures by physical adsorption is a great challenge in the chemical industry. Herein, we report a GeF 6 2- anion embedded MOF (ZNU-6) with customized pore structure and pore chemistry for benchmark one-step C 2 H 4 recovery from C 2 H 2 and CO 2 . ZNU-6 exhibits significantly high C 2 H 2 (1.53 mmol/g) and CO 2 (1.46 mmol/g) capacity at 0.01 bar. Record high C 2 H 4 productivity is achieved from C 2 H 2 /CO 2 /C 2 H 4 mixtures in a single adsorption process under various conditions. The separation performance is retained over multiple cycles and under humid conditions. The potential gas binding sites are investigated by density functional theory (DFT) calculations, which suggest that C 2 H 2 and CO 2 are preferably adsorbed in the interlaced narrow channel with high aff0inity. In-situ single crystal structures with the dose of C 2 H 2 , CO 2 or C 2 H 4 further reveal the realistic host-guest interactions. Notably, rare C 2 H 2 clusters are formed in the narrow channel while two distinct CO 2 adsorption locations are observed in the narrow channel and the large cavity with a ratio of 1:2, which accurately account for the distinct adsorption heat curves.