Antifouling properties of poly(vinylidene fluoride)-incorporated cellulose acetate composite ultrafiltration membranes

Abstract

Poly(vinylidene fluoride) (PVDF) was incorporated in Cellulose acetate (CA) to prepare polymeric blend membrane to enhance the antifouling properties and rejection. Blend membranes consist of different concentrations (0, 2.5 and 5.0 wt%) of polyvinylpyrrolidone (PVP), which was the hydrophilic polymer additive and pore forming agent. The existence of membrane functional groups was analyzed by ATR-FTIR spectroscopy. AFM and SEM were conducted to explain the surface morphology of the synthesized blend membranes. Membrane properties were examined by contact angle, porosity and equilibrium water content (EWC). The membranes thermal and mechanical properties were determined by performing TGA and tensile test. Membrane performance was assessed by pure water flux (PWF), rejection, antifouling properties using bovine serum albumin (BSA) and Sodium alginate (SA) solution. In this study, CPA-2 membrane showed high PWF of 269.82 L m−2 h−1, flux recovery ratio (FRR) against BSA and SA was 94% and 92%, respectively. Rejection of BSA and SA was found to be 83% and 86%, respectively. From the results, it was significant that the hydrophilic additive PVP blended membrane ameliorated and showed better results in surface roughness, hydrophilicity, thermal and mechanical stability. Hence, CPA-2 membrane would exhibit less susceptibility to fouling with enhanced PWF, permeability and selectivity.