Molecular Sieving Separation of Hexane Isomers by an Aluminum‐Based Metal‐Organic Framework with nia Topology

Comprehensive Summary Aluminum‐based metal‐organic frameworks (Al‐MOFs) feature low density, high stability, and non‐toxicity, making them highly promising for adsorption‐related applications. In this study, we report the construction of a novel nia‐type Al‐MOF based on 6‐connected trinuclear Al 3 clusters, HIAM‐341, employing an isophthalate‐derived hexatopic linker. It exhibits a robust structure with a BET surface area of 1094 m 2 ·g –1 , with a pore size of 4.7 Å. HIAM‐341 demonstrates size‐sieving separation of hexane isomers, with adsorption capacities of 164 and 54 mg·g –1 for n ‐hexane and 3‐methylpentane at 303 K and 1 bar, respectively, while excluding 2,2‐dimethylbutane. Multicomponent breakthrough experiments further confirm its separation capability, and the underlying selective molecular exclusion mechanism has been uncovered by DFT calculations. Our research provides new insights into the rational design of robust Al‐MOFs with tailored pore structures by employing organic linkers with high coordination density for targeted separations.