Electro‐field alignment in a novel metal–organic framework for benchmark separation of ethylene from a ternary gas mixture

Abstract

One‐step separation of C2H4 from ternary gas mixtures containing acetylene (C2H2), ethylene (C2H4), and carbon dioxide (CO2) represents a great challenge in chemical industry. Herein, we report the electro‐field alignment in a novel anion‐pillared MOF (SIFSIX‐TEPE‐Cu) for benchmark C2H4 separation from C2H2/CO2/C2H4 gas mixtures. The semi‐cage cavities featuring capped facets generated negative potentials along anion pillars and compensatory positive‐charged electro‐fields along organic ligands (TEPE) that facilitate specific recognitions of C2H2 and CO2 over C2H4. As a result, SIFSIX‐TEPE‐Cu exhibits high adsorption capacities for C2H2 (123 cm3 g−1) and CO2 (65 cm3 g−1) at 1.0 bar and 298 K. Notably, the record‐high C2H2 uptake (78 cm3 g−1) at 0.01 bar and remarkable C2H2/C2H4 selectivity (615.2) renders benchmark trace C2H2 removal ability. Dynamic breakthrough experiments demonstrate the benchmark productivity for high‐purity C2H4 (>99.995%) of 194.7 mol kg−1 and 5.96 mol kg−1 from binary C2H2/C2H4 (1/99, v/v) and ternary C2H2/CO2/C2H4 (1/9/90, v/v/v) gas mixtures.