Integration of Simulation and Experimental Approaches for Optimizing TiO2 Nanowire/Fe2O3 Modified Polyethersulfone Membranes in Dye Removal Applications

Abstract

This study aimed to mimic and optimize polyethersulfone (PES) membrane performance for dye separation applications. Bulk modification was conducted, harnessing titanium dioxide nanowire/iron oxide (TiO₂ NW/Fe₂O₃) to improve water flux, dye removal efficiency, and antifouling properties. Membranes were fabricated with varying nanostructure concentrations (0.1-0.7 g) and examined under different pH levels (3-12) and dye concentrations (25-100 mg/L). Utilizing the response surface methodology (RSM), the process conditions optimized with ANOVA confirmed the adopted model reliability (R² = 0.9668 for flux, 0.9809 for rejection). Experimental results revealed that 0.7 g of TiO₂ NW/Fe₂O₃ achieved the highest performance, recording 93 L/m²∙h flux and >99% naphthol blue black dye rejection. Besides, increasing nanostructure content has enhanced the membrane porosity and hydrophilicity. Meanwhile, acidic conditions (pH 3-5) facilitated stronger dye–membrane interactions, while alkaline pH reduced the retention efficiency. Simulation results validated the experimental findings, bestowing deeper insights into the dye separation mechanisms. These findings highlighted the potential of TiO₂ NW/Fe₂O₃-modified PES membranes as a promising candidate for wastewater treatment applications.