Preparation of PVDF-TiO₂ mixed-matrix membrane and its evaluation on dye adsorption and UV-cleaning properties

In this study, the polyvinylidene fluoride (PVDF)-Titanium dioxide (TiO₂) mixed-matrix membranes were prepared via phase inversion technique. The properties of PVDF-TiO₂ mixed-matrix membranes were characterized based on pore size distribution, membrane porosity, field emission scanning electron microscope (FESEM) and photocatalytic behavior. The hydrophilicity of the mixed-matrix membrane was enhanced and resulted in the improved pure water permeability (392.81±10.93l/m²hbar) compared to that 76.99±4.87l/m²hbar of the neat membrane. The neat and mixed-matrix membranes were further investigated in terms of filtration, adsorption and UV-cleaning properties based on methylene blue (MB) solution. Mixed-matrix membranes showed excellent removal efficiency (∼99%) when sodium dodecyl sulfate (SDS) was introduced into the MB feed solution. The produced mixed-matrix membrane shows some slight photocatalytic properties improvement as FTIR results reviewed that the cleavage of CN bonding due to MB adsorption reduced more significantly with the presence of TiO₂ NPs and ultraviolet (UV) light irradiation. The UV-cleaning properties of the mixed-matrix membrane were further proved by the 100% flux recovery ratios (FRRs) for mixed-matrix membrane, suggesting that the embedded TiO₂ NPs was photocatalytically active and able to degrade the adsorbed MB in the membrane.