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DOE OSTI · 2419249

Pore Aperture Control Toward Size‐Exclusion‐Based Hydrocarbon Separations

Lal, Bhajan·Idrees, Karam B.·Xie, Haomiao·Smoljan, Courtney S.·Shafaie, Saman·Islamoglu, Timur·Farha, Omar K.
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Abstract

Metal–organic frameworks (MOFs) have been proposed as a promising material for non-thermal chemical separations owing to their high structural diversity and tunability. Here, we report the synthesis of a zinc-based MOF containing a three-dimensional (3D) linker, bicyclo[2.2.2]octane-1,4-dicarboxylic acid, with high thermal stability towards the separation of hexane isomers. The incorporation of the 3D linker enhances the structural stability and provides well-defined pore apertures/channels with sub-Ångstrom precision. This precision allowed for the separation of similarly sized hexane isomers based on subtle differences in their kinetic diameters. Multi-component liquid phase batch experiments confirmed the separation of hexanes mixture into linear, monobranched, and dibranched isomers. This work represents a significant milestone in the construction of stable Zn-based MOFs and the incorporation of 3D linkers as a potential solution to challenging separations.

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37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRYChemistryZn-MOFhexanesmetal-organic frameworksseparation

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Lal, Bhajan, Idrees, Karam B., Xie, Haomiao, Smoljan, Courtney S., Shafaie, Saman, Islamoglu, Timur, Farha, Omar K.. 2023-02-15. Pore Aperture Control Toward Size‐Exclusion‐Based Hydrocarbon Separations. https://doi.org/10.1002/anie.202219053

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