ADVANCEMENTS IN POLYSULFONE MEMBRANE TECHNOLOGY FOR EFFICIENT H2S AND CO2 SEPARATION FROM CH4: A COMPREHENSIVE REVIEW

Abstract

Natural gas streams frequently contain carbon dioxide (CO₂) and hydrogen sulfide (H₂S), which cause corrosion, safety hazards, and environmental concerns, necessitating efficient separation technologies. Membrane-based processes have gained increasing attention due to their energy efficiency and operational simplicity, with polysulfone (PSF)-based membranes emerging as promising candidates because of their thermal stability, mechanical strength, and tunable transport properties. Despite their extensive studies on CO₂/CH₄ separation, research addressing the separation of CO₂ and H₂S from CH₄ under sour gas conditions remains limited and fragmented. This review critically evaluates recent advances in PSF-based membrane technologies for CO₂ and H₂S separation from natural gas, with particular emphasis on fabrication routes such as solution casting and phase inversion, characterization techniques, and gas permeation analysis. To address this gap, a literature calibrated predictive analytical framework is proposed that systematically links experimentally verifiable indicators like morphology, polymer-filler interfacial integrity, chemical interactions, chain mobility, thermal stability, and plasticization resistance to membrane design robustness. Recent findings demonstrate that hybrid architectures, particularly PSF-based mixed matrix membranes (MMM), incorporating functionalized fillers such as zeolitic imidazolate frameworks (ZIFs), graphene oxide, metal organic frameworks (MOFs), and ionic liquids, significantly enhance permeability, selectivity, and long term stability. The integration of molecular simulations and machine learning is highlighted as a promising pathway towards predictive membrane design and accelerated material screening for sour gas separation.