Benzenesulfonamide-Functionalized Electrospun Polysulfone as an Antibacterial Support Layer of Thin-Film Composite Pressure-Retarded Osmosis Membrane: Fabrication and Performance Evaluation

This study explores the utilization of electrospun polysulfone (PSF) as a thin-film support in the pressure-retarded osmosis (PRO) system, leveraging its notable thermal, chemical, and oxidative stability. To enhance the efficiency of the PRO system, the inherently hydrophobic PSF surface is modified through functionalization with benzenesulfonamide groups (BSA-PSF). The modification process involves chloromethylation of PSF, followed by substitution with BSA, and subsequent electrospinning to produce BSA-PSF fibers. A thin-film composite forward osmosis membrane, composed of an electrospun BSA-PSF support layer and a polyamide thin layer synthesized through interfacial polymerization (BSA-PSF/PA), is developed. The incorporation of BSA improves the hydrophilicity of the membrane surface, while also imparting antibacterial features to the electrospun BSA-PSF. Comparative analyses with pristine PSF membranes reveal that the pure water flux of the BSA-PSF membrane achieves a notable 65 LMH, surpassing the pristine PSF membrane’s flux of 45 LMH. Moreover, protein absorption is significantly reduced in the BSA-PSF membrane (40.6 μg cm⁻²) compared to the unmodified PSF membrane (64.2 μg cm⁻²). The establishment of a hydration layer near the surface, facilitated by hydrogen interactions between water units and the hydrophilic sulfonamide chains in the polymer, contributes to lower protein adsorption than observed in the pristine PSF membrane. Notably, the prepared BSA-PSF/PA membrane exhibits advanced surface hydrophilicity, commendable antibacterial properties, exceptional fouling resistance, and high water permeability. These attributes position it as a promising candidate for widespread applications in power generation and large-scale water treatment.

Graphical Abstract

BSA functionalized the electrospun PSF used as the PRO membrane’s thin-film support. The introduction of BSA to PSF improved the hydrophilicity, water flux, antibacterial properties, and fouling resistance of thin-film composite PRO membrane