Fabrication and Performance Evaluation of NiMOF@MGO-Modified Polysulfone Membranes for Heavy Metal Removal from Wastewater

This work presents a detailed analysis of polysulfone (PSF) based mixed matrix membranes (MMMs) modified with NiMOF@MGO for water purification. Magnetic iron oxide nanoparticles were synthesized and incorporated into the NiMOF@GO framework, with successful formation confirmed by FT-IR, XRD, BET, TGA, and SEM analyses. Membranes were prepared via phase inversion and modified with varying NiMOF@MGO contents. SEM, AFM, and contact angle analyses demonstrated enhanced membrane hydrophilicity with increasing MOF concentration, reducing the contact angle from 59.74° (0.05 wt%) to 49.70° (0.2 wt%). The highest flux of 117.85 L/m²·h was observed for the PMM-0.2 membrane. Heavy metal removal was most efficient at pH 6, with the PMM-0.1 membrane achieving 95.97% and 95.92% rejection for Pb²⁺ and Cu²⁺, respectively. In oil-water separation, PMM-0.1 exhibited optimal performance, with a water flux of 45.84 L/m²·h. Antifouling tests showed the PMM-0.2 membrane had the highest flux recovery of 85.97%, indicating improved fouling resistance. Overall, incorporation of NiMOF@MGO significantly enhanced membrane hydrophilicity, flux, selectivity and antifouling performance, demonstrating its potential for advanced water purification applications.