Effect of Polyvinylpyrrolidone on Polyvinylidene Fluoride/Hydroxyapatite-Blended Nanofiltration Membranes: Characterization and Filtration Properties

Introduction: The application of polyvinylidene fluoride (PVDF) as a filtration membrane is limited due to its hydrophobicity. This paper elaborated on the fabrication process of nanofiltration PVDF membrane incorporating various quantities of hydrophilic polyvinylpyrrolidone (PVP) and hy-droxyapatite (HA) using a wet phase inversion method to improve its hydrophilicity. Methods: The membrane was fabricated by using the wet phase inversion method. It was then charac-terized in terms of water permeability, water contact angle, water content, surface energy, and surface porosity. Bacteria and Fe ions filtration was conducted to investigate the membrane filtration perfor-mance. Results: The PVDF/PVP/HA-blended membrane showed the highest water permeability (6,165 LMH/Bar), water content (45.2 %), and surface energy (104.1 mN/m) when 2 wt.% of PVP was intro-duced into the base polymer PVDF. This fabricated membrane, labeled as PVP 2.0, also showed the lowest contact angle (64°) and the highest surface porosity (42%). Conclusion: Overall, the PVP introduction patents into the polymeric membrane doping solution potentially improves membrane hydrophilicity and permeability.