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

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 cm(3) g(-1)) and CO2 (65 cm(3) g(-1)) at 1.0 bar and 298 K. Notably, the record-high C2H2 uptake (78 cm(3) 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.