Advancement in modification of polyvinylindene fluoride hollow fiber membrane contactors for CO₂ capture

Membrane contactors are well-designed, environmentally friendly, waste free technology which have been of great interest in area of gas separations. Polyvinylidene fluoride (PVDF) is promising membrane contactor material characterized with high hydrophobicity, high solubility in wide range of solvents and good chemical resistance. In spite of the viability and merits, key intrinsic issue with PVDF membranes contactor is membrane wetting that consequently results in increase in mass transfer-resistance, membrane flux deteriorations and decline in overall long-term stability performances. Different modification methods and strategies that involve alterations of surface chemistry and structures have been identified to mitigate wetting issue. The intention of modification tactics is to enhance surface’s hydrophobicity of PVDF contactor membranes thereby controlling membrane wetting. This review presents the approaches previously adopted for PVDF membranes modifications. The progresses besides performances of the modified PVDF membranes in area of gas separations are discussed. Lastly, challenges in addition to outlooks of modified PVDF membrane for membranes contactor were highlighted. This review has brought into limelight the methods and the justifications for PVDF membrane modifications geared towards effective performances of PVDF membranes contactors for CO₂ absorption.