Ethane Triggered Gate‐Opening in a Flexible‐Robust Metal‐Organic Framework for Ultra‐High Purity Ethylene Purification

Abstract Priority recognition separation of inert and larger ethane molecules from high‐concentration ethylene mixtures instead of the traditional thermodynamic or size sieving strategy is a fundamental challenge. Herein, we report ethane triggered gate‐opening in the flexible‐robust metal‐organic framework Zn(ad)(min), the 3‐methylisonicotinic acid ligand can spin as a flexible gate when adsorbing the cross‐section well‐matched ethane molecule, achieving an unprecedented ethane adsorption capacity (62.6 cm 3 g −1 ) and ethane/ethylene uptake ratio (3.34) under low‐pressure region (0.1 bar and 298 K). The ethane‐induced structural transition behavior has been uncovered by a collaboration of single‐crystal X‐ray diffraction, in situ variable pressure X‐ray diffraction and theoretical calculations, elucidating the synergetic mechanism of cross‐section matching and multiple supramolecular interactions within the tailor‐made pore channels. Dynamic breakthrough experiments have revealed the outstanding separation performance of Zn(ad)(min) during the production of ultra‐high purity ethylene (>99.995 %) with a productivity of up to 39.2 L/kg under ambient conditions.