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Updated: Aug 27, 2025
Author Spotlight: Accelerating Discovery in Microporous Material Chemistry
Published on: October 6, 2023
Efficient Splitting of Alkane Isomers by a Bismuth-Based Metal-Organic Framework with Auxetic Reentrant Pore
Zhaoqiang Zhang1, Shing Bo Peh1, Chengjun Kang1
1Department of Chemical and Biomolecular Engineering, National University of Singapore, 117585, Singapore, Singapore.
Abstract:
The isolation of di-branched alkanes from their isomers is vital in gasoline upgrading to achieve high octane numbers but is significantly challenging and energy-intensive. Here, we report the highly efficient separation of hexane isomers by combing molecular recognition and size-sieving in a bismuth-based MOF, UU-200. The unique auxetic structure with reentrant honeycomb-like pore cavities connected by narrow pore windows endows UU-200 with a complete rejection of di-branched alkanes and high capacities for linear and mono-branched isomers. The molecular sieving effect, unprecedented separation selectivities, and excellent efficiencies are proved via adsorption isotherms and breakthrough experiments with high research octane numbers obtained (>96), indicating a benchmark for alkane separation under ambient conditions. The molecular recognition mechanism was unveiled by theoretical simulation and in situ Fourier-transform infrared spectroscopy.
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