Investigation and characterization of TiO2-TFC nanocomposite membranes; membrane preparation and UV studies

Abstract

The purpose of this study was to compare the presence or absence of UV irradiation on the separation performance and morphology of the TiO₂-assembled thin film membranes (in different concentrations). Furthermore, an attempt was made to show and compare the effect of the presence of TiO₂ nanoparticles in aqueous and organic phases during the interfacial polymerization process. SEM, zeta potential, water contact angle, and other characterization methods like the molecular weight cut-off (MWCO), as well as antifouling measurements and the separation ability tests were utilized to characterize the thin layer properties. SEM images showed an integrated distribution of the nanoparticles under the PA skin layers. The rejection capability against the sugars was increased with the growth of TiO₂ concentration in the absence of UV. Accordingly, the MWCO of the membranes changed from 420 Da to less than 150 Da. In this case, the flux recovery ratio significantly enhanced while the surface negative charge increased. On the other hand, the membrane pore sizes increased under UV irradiation. Changes in flux and separation performance were significant and considerable during the lack of UV irradiation in comparison with using UV.