Hopping Diffusion in Wiggling Nanopore Architecture of MOF Enabling Synergistic Equilibrium‐Kinetic Separation of Fluorinated Propylene and Propane
Wei Xia, Zhijie Zhou, Chun Xia, Lihang Chen, Liangzheng Sheng, Zheng Fang, Zhiguo Zhang, Qiwei Yang, Qilong Ren, Zongbi Bao
Abstract
Abstract The separation of octafluoropropane (C 3 F 8 ) from hexafluoropropylene (C 3 F 6 ) is an industrially important yet challenging process due to their similar physicochemical properties and stringent purity demands in industrial applications. Herein, we address this task through precise pore architecture in a zirconium‐based metal‐organic framework (Zr‐PMA), which exhibits unique “wiggling nanopores” with narrow windows and large cavities. The narrow windows act as diffusion barriers, selectively restricting C 3 F 8 transport, while the large cavities provide strong adsorption sites for C 3 F 6 , enabling an equilibrium‐kinetic synergistic separation. This dual functionality results in a ∼450‐fold difference in diffusion rates and exceptional kinetic selectivity for C 3 F 6 over C 3 F 8 , as demonstrated by adsorption isotherms, time‐resolved kinetics, and dynamic breakthrough experiments. Theoretical calculations coupled with in situ spectroscopy elucidate the pore geometry‐dependent hopping diffusion mechanism responsible for the separation. This work establishes wiggling pore geometry as a versatile paradigm for advanced adsorbents targeting energy‐efficient separations of structurally similar fluorocarbon mixtures.