Construction of Negative Electrostatic Pore Environments in a Scalable, Stable and Low‐Cost Metal‐organic Framework for One‐Step Ethylene Purification from Ternary Mixtures

Abstract

AbstractOne‐step separation of C2H4 from ternary C2 mixtures by physisorbents remains a challenge to combine excellent separation performance with high stability, low cost, and easy scalability for industrial applications. Herein, we report a strategy of constructing negative electrostatic pore environments in a stable, low‐cost, and easily scaled‐up aluminum MOF (MOF‐303) for efficient one‐step C2H2/C2H6/C2H4 separation. This material exhibits not only record high C2H2 and C2H6 uptakes, but also top‐tier C2H2/C2H4 and C2H6/C2H4 selectivities at ambient conditions. Theoretical calculations combined with in situ infrared spectroscopy indicate that multiple N/O sites on pore channels can build a negative electro‐environment to provide stronger interactions with C2H2 and C2H6 over C2H4. Breakthrough experiments confirm its exceptional separation performance for ternary mixtures, affording one of the highest C2H4 productivity of 1.35 mmol g−1. This material is highly stable and can be easily synthesized at kilogram‐scale from cheap raw materials using a water‐based green synthesis. The benchmark combination of excellent separation properties with high stability and low cost in scalable MOF‐303 has unlocked its great potential in this challenging industrial separation.