Kinetic Effect Intensified Thermodynamic Separation of Ethane via Low‐Cost but Effective Metal‐Organic Frameworks for Ethylene Purification

ABSTRACT Ethylene purification via ethane/ethylene (C 2 H 6 /C 2 H 4 ) adsorptive separation faces challenges of the trade‐off between selectivity and desorption energy consumption, and high adsorbent costs. Herein, we propose a strategy integrating localized kinetic confinement effects with thermodynamic equilibrium separation to design a low‐cost nickel‐based metal‐organic framework (PY‐MOF) using affordable ligands. PY‐MOF features a rhombic pore structure with accessible N/O adsorption sites at the corners. Amplifying the slight molecular size and configuration difference, it achieves kinetic discrimination, while synergistic moderate C‐H∙∙∙N/O hydrogen bonding and weak van der Waals interactions enhance thermodynamic affinity toward C 2 H 6 . At 298 K and 1 bar, PY‐MOF exhibits an ideal adsorption solution theory (IAST) selectivity of 2.46 for C 2 H 6 /C 2 H 4 (50/50, v/v). Dynamic breakthrough experiments demonstrate one‐step production of polymer‐grade ethylene from binary mixtures, achieving a maximum productivity of 19.27 L kg −1 . More importantly, it costs only 7.82 USD kg −1 , with a performance/cost ratio of 1.13, could be efficiently regenerated at 80°C for 3 h, and maintains excellent stability across wide humidity, solvent, and pH ranges. This work provides a benchmark low‐cost, high‐performance MOF for challenging C 2 H 6 /C 2 H 4 separations, offering a new paradigm for adsorbent design in C 2 H 4 purification.