Precise Kinetic Separation of Hexane Isomers via Morphology Engineering of Metal–Organic Frameworks with Diffusion‐Selective Pore Structure

Abstract Hexane isomer separation is critical to advancing sustainable and high‐value refining in the petrochemical industry. However, precise separation of multi‐component hexane mixtures with similar molecular structures remains a bottleneck. Herein, we report a novel metal–organic framework (Cu‐3,3‐bipyridine‐SIFSIX, termed as ZU‐621) featuring a tailored diffusion‐selective pore structure, synergistically integrated with crystal size engineering, that enables precise and efficient separation of hexane isomers. Owing to the uniquely engineered dumbbell‐shaped, misaligned electronegative pore environment, ZU‐621 exhibits intrinsic kinetic discrimination among hexane isomers based on the alkyl spatial distribution. Complementary crystal morphology engineering further fine‐tunes the adsorption–diffusion behavior, affording precise kinetic separation across linear, mono‐branched, and di‐branched isomer pairs. As a result, this kinetic‐morphology synergistic approach achieved benchmark separation performance as evidenced by record gasoline productivity (research octane numbers, RON > 95, 49.8 L kg −1 ) along with precise, multi‐objective separation across five hexane isomers.