Phosphoric Acid-Modified TiO2 Nanoparticles as Functional Additives for High-Performance Polyethersulfone Ultrafiltration Membranes.

Polyethersulfone (PES) ultrafiltration membranes were modified with phosphoric acid-functionalized TiO2 nanoparticles (0-1 wt%) via phase inversion to enhance permeability, antifouling performance, and dye removal for wastewater treatment. Structural and morphological analyses confirmed the successful modification and uniform incorporation of TiO2 within the PES matrix. The membrane containing 0.5 wt% TiO2 exhibited optimal performance, achieving the lowest contact angle (~39°), highest porosity (~65.5%), and maximum pure water flux (~292 L·m-2·h-1), compared to 204 L·m-2·h-1 for pristine PES. Rhodamine B rejection exceeded 85%, driven by electrostatic interactions between phosphate groups and cationic dye molecules. Fouling tests using bovine serum albumin revealed a high FRR (~92%) and reduced irreversible fouling. Excessive TiO2 loading led to nanoparticle agglomeration and reduced permeability.