Noble gases and microporous frameworks; from interaction to application

The noble gas storage and separation capability of three classes of microporous frameworks (MFs) including Metal–Organic Frameworks (HKUST-1 and MFU-4l), Covalent-Organic Frameworks (COF-102) and Zeolite Imidazolate Frameworks (ZIF-8) were studied using thermal desorption spectroscopy (TDS). The maxima in the TDS spectra were correlated to the adsorption sites and strength of interactions. The difference in the final desorption temperature for xenon and krypton was correlated to the separation capability of the frameworks. The results show that MFU-4l and HKUST-1 are potential candidates for separation and storage of krypton and xenon. Further sorption studies have proved the ability of both candidates in Kr/Xe separation in larger scale.

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► Xe and Kr adsorption in different classes of microporous frameworks.
► Thermal desorption spectroscopy and adsorption isotherm measurements.
► Correlating the desorption data to uptake and separation capability.
► Selection of potential structures with high performance in Xe/Kr separation.
► Isosteric heat of adsorption for Xe/Kr in potential candidates.