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

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.The authors are grateful for the funding of the Spanish AEI through the projects PID2021-123120OB-I00 and PID2019-104369RB-I00 and the funding of European Union through the projects “HYLANTIC”-EAPA_204/2016, which is co-financed by the European Regional Development Fund in the framework of the INTERREG Atlantic program, and the Project ENERGY PUSH SOE3/P3/E0865, which is co-financed by the European Regional Development Fund (ERPF) in the framework of the INTERREG SUDOE Programme. Gonzalo Moral is grateful to the FPU postgraduate research grant awarded by the Spanish Ministry of Science and Innovation. The authors thank for technical and human support provided by SGIker (UPV/EHU/ERDF, EU) and LADICIM (University of Cantabria)