A Robust Zeolitic Imidazolate Framework Membrane with High H2/CO2 Separation Performance under Hydrothermal Conditions

Abstract

An upsurge in searching membranes with high selectivity, permeability, and stability, which have been considered to be promising in the membrane-based gas separation process, has received huge attentions in academia and industry. In this work, we demonstrated a new molecular sieving ZIF membrane, which has a unique mixed-ligand ZIF structure constructed by two bulk imidazolate linkers within the zeolite GIS topology, resulting in appropriate aperture size, strong affinity to CO2, exceptional thermal and chemical stabilities, and superhydrophobic properties. Benefited from these features, the resulting JUC-160 membrane indeed exhibited remarkable separation efficiency and stability, with excellent H2/CO2 selectivity of 26.3 and considerable H2 permeance of 9.75 × 10-7 mol m-2 s-1 Pa-1 under high temperature up to 200 °C. Furthermore, owing to its superhydrophobicity, the JUC-160 membrane could maintain its prominent separation performance even with the presence of steam.