Antifouling properties of novel PSf and TNT composite membrane and study of effect of the flow direction on membrane washing

Abstract

Antifouling properties of the polysulfone (PSf) and titanium nanotube (TNT) mixed matrix ultrafiltration membrane were investigated. The membrane was prepared by phase separation process using different concentrations of TNT and PSf. The pure water flux, protein removal and fouling parameters were studied to analyze the performance of the membrane. Morphology of the membrane was characterized by using scanning electron microscopy and atomic force microscopy. The most prominent observation was the significant improvement in water flux which attributed to improved hydrophilicity. The improvement of hydrophilicity was confirmed by water contact angle measurement and porosity measurements. This improvement in hydrophilicity is because of hydroxyl group present on TNT as determined by ATR-IR spectra. Fouling resistance of the membranes assessed by BSA solution filtration showed that 0.3 and 0.5 wt.% TNT loading membrane exhibited the best antifouling property that resulted in 100% flux recovery. The results also showed that 0.3 wt.% TNT loading membrane possessed the highest mean pore radius, porosity, and water flux. The effect of different washing directions in fouling experiment was reported. The perpendicular washing and parallel washing were carried out during fouling experiment and effects were discussed. The TNT nanocomposite membrane with parallel washing showed significant reusability during filtration.