Hydrogen recovery from industrial waste streams using Matrimid®/ZIF mixed matrix membranes

Abstract

This work reports the performance of Mixed Matrix Membranes (MMMs) for hydrogen purification. ZIF-8 and ZIF-90 Zeolitic Imidazole Frameworks (ZIFs) have been used as additives to improve the separation performance of the pristine Matrimid® polymeric membrane. The good interfacial contact and distribution of the filler along the membrane have been determined by electronic microscopy and the comparison of the membrane's performance is done in terms of hydrogen permeability and selectivity from industrial waste streams. The results showed that MMMs almost double H2 permeability (50 Barrer) and increase H2 selectivity (H2/CO2: ⩯4.3, H2/N2: ⩯35, H2/CO: ⩯41, H2/CH4: ⩯36) compared to the pristine polymeric membrane. Finally, the influence of the feed composition (by means of binary and multicomponent mixtures) and temperature (30, 50 and 80 °C) as operating variables has been analysed. The permeability was stable in the wide range of feed compositions while the increase in temperature resulted in lower selectivity and higher permeability.