Preparation and performance of PVDF-based nanocomposite membrane consisting of TiO2 nanofibers for organic pollutant decomposition in wastewater under UV irradiation

Polyvinylidene Fluoride (PVDF) nanocomposite membrane consisting of electrospun titanium dioxide (TiO2) nanofibers (PVDF/e-TiO2) was prepared by hot pressing the as-spun TiO2 nanofibers onto PVDF flat sheet membrane. The TiO2 nanofibers act as a photocatalyst to decompose organic pollutants present in wastewater under UV irradiation, while PVDF membrane acts as a support. The hot press technique was carried out by applying the operating temperatures at 100°C, 160°C and 180°C for 30min. The nanocomposite membrane was characterized by FESEM, EDX, contact angle measurement, DSC, and UV–Vis–NIR spectroscopy. The FESEM images and EDX analysis showed good adhesion and dispersion of TiO2 nanofibers in PVDF membrane. The hot-pressed PVDF/e-TiO2 membrane at lower temperature (100°C) (PVDF/e-TiO2-100) is more hydrophilic, higher pure water flux and has higher UV absorbance compared to the PVDF/e-TiO2-160 and PVDF/e-TiO2-180 membranes. The concentration of bisphenol A (BPA) in the feed solution was found to reduce with the degradation percentage of 63% to 85% after the PVDF/e-TiO2 nanocomposite membrane was treated with UV radiation. The results indicated that the introduction of TiO2 nanofibers in PVDF-based nanocomposite membrane via hot pressing indeed plays an important role towards enhancing the degradation and filtration of organic pollutants such as BPA.