Functionalized PAN Membranes: Tackling Fouling in Water Purification Systems

Access to clean drinking water is a critical global challenge due to contamination with industrial effluents, drugs, and pathogens. Polyacrylonitrile (PAN) membranes are widely used for water purification, but their susceptibility to fouling limits efficiency and lifespan. In this study, a sustainable and efficient UV-grafting process was employed to modify PAN membranes, to achieve antifouling and antimicrobial properties.

Cationic and zwitterionic methacrylate-based monomers, including ammonium, ammonium alcohol, N-oxide, carboxybetaine, sulfobetaine, and phosphobetaine groups, were grafted onto the membrane surface using photoinitiators such as bisacylphosphine oxide (BAPO) and lithium acylphosphinate (LAP). The modified membranes were characterized using FTIR, XPS, SEM-EDX, AFM, zeta potential analysis, permeability testing, molecular weight cut-off measurements, dye adsorption assays, porosity, and pore size analysis.

Microbiological evaluation revealed antifouling properties and/or antimicrobial activity depending on the immobilized functional polymer. These findings demonstrate the potential of UV-grafted PAN membranes to mitigate fouling and extend membrane longevity, offering a green and efficient solution for sustainable drinking water treatment.