Fluorinated polymer membranes for separation of industrial gas mixtures

摘要: Polymeric membranes acquire enhanced barrier properties including permeability and selectivity besides improved chemical and thermal stabilities, when they undergo surface fluorination. Commercially available ion exchange membranes, state of the art Reverse Osmosis membranes besides polyethersulfone were subjected to direct fluorination to modify membrane performance. Gas permeation properties of pure O2, N2, H2 and CO2 gases through fluorinated membranes and influence of fluorination duration on the separation performance is investigated. Indigenously synthesized polyethersulfone membrane fluorinated for 5 min was selected to further study the effect of feed pressure as they had exhibited better pure gas permeability for O2/N2, H2/N2 and H2/CO2 systems. The physiochemical properties, intermolecular interactions and surface morphology of modified membranes are examined by water sorption, FTIR, Wide Angle X-ray Diffraction (WAXRD) and SEM. Fluorinated membranes can be successfully used for the O2 enrichment from air for medical applications, recovery of H2 from refinery off gases and power plant exit gas.