Characterization of self-cleaning RO membranes coated with TiO2 particles under UV irradiation

Fouling is one of the most important problems in almost all membrane processes. Many attempts have been made to minimize fouling. In this research, the effects of coating of membrane surface with TiO2 particles and UV radiation in creating self-cleaning membrane have been studied. Coating the membrane surface with TiO2 particles not only creates photocatalytic property but also increases membrane hydrophilicity. Surface coating was carried out by self-assembly of TiO2 particles through coordinance bonds with OH functional groups of polymer on the membrane surface. The flux of the coated membrane with TiO2 particles after being radiated by UV light was increased significantly in comparison with a virgin membrane. This fact indicates that the self-cleaning property have been created by TiO2 particles on the surface of membrane. To investigate the effect of different parameters in increasing the self-cleaning property of the membrane, the concentration of TiO2 particles, duration of UV radiation, duration of being kept in water, membrane roughness and the presence of SiO2 particles have been studied.