Polymer‐Stabilized Percolation Membranes Based on Nanosized Zeolitic Imidazolate Frameworks for H 2 /CO 2 Separation

This work shows the preparation of self‐supported composite membranes prepared with the nano‐sized zeolitic imidazolate frameworks (ZIFs): ZIF‐8, ZIF‐7(III) and ZIF‐7/8 core‐shells. The membranes consist of compressed pellets of ZIF nanoparticles (up to 74 wt% loading) stabilized with gas‐impermeable epoxy resin, providing a gas transport‐selective percolation network named polymer‐stabilized percolation membrane (PSPM). The different PSPMs have been characterized by SEM, TGA, XRD, FTIR and Raman. FIB/SEM has provided a 3D reconstruction of the composite thanks to the slice and view technique, allowing a perfect visualization of the inside of the network. The N 2 adsorption properties have also been studied and compared with those of ZIFs in powder state. The gas separation performance of these membranes has been tested for the H 2 /CO 2 mixture. The PSPMs were tested with feed pressures up to 5 bar, obtaining H 2 permeabilities of hundreds of Barrer and a maximum H 2 /CO 2 selectivity of 12.3.