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Oriented and penetrating molecular sieving membranes display enhanced separation performance. A polyimide (PI) solution containing highly dispersed ZIF-7(III) sheets in CHCl 3 was deposited on a glass side and subjected to flat-scraping with a membrane fabricator. In this way we developed a novel oriented and penetrating ZIF-7@PI mixed matrix membrane (MMM) with 50 wt. % ZIF-7 loading. Because the height of the ZIF-7 sheets (5 μm) is higher than the film thickness, every ZIF-7 sheet penetrates both surfaces of the polyimide film. Since the ZIF-7 channels are the dominant pathway for gas permeation, the ZIF-7@PI MMM displays a high molecular sieve performance for the separation of H 2 (0.29 nm) from larger gas molecules. At 100 °C and 2 bar, the mixture separation factors of H 2 /CO 2 and H 2 /CH 4 are 91.5 and 128.4, with a high H 2 permeance of about 3.0×10 -7  mol m -2  s -1  Pa -1 , which is promising for hydrogen separation by molecular sieving., (© 2019 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Separation of p-xylene (kinetic diameter ca. 0.58 nm) from its bulkier isomers (o-xylene and m-xylene, ca. 0.68 nm) is challenging, but important in the petrochemical industry. Herein, we developed a highly selective and stable metal-organic framework (MOF) MIL-160 membrane for selective separation of p-xylene from its isomers by pervaporation. The suitable pore size (0.5∼0.6 nm) of the MIL-160 membrane selectively allows p-xylene to pass through, while excluding the bulkier o-xylene and m-xylene. For the separation of equimolar binary p-/o-xylene mixtures at 75 °C, high p-xylene flux of 467 g m -2  h -1 and p-/o-xylene selectivity of 38.5 could be achieved. The stability of MIL-160, ensured the separation performance of the MIL-160 membrane was unchanged over a 24 h measurement. The high separation performance combined with its high thermal and chemical stability makes the MIL-160 membrane a promising candidate for the separation of xylene isomers., (© 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)