Partially coated TiO2 on Al2O3 membrane for high water flux and photodegradation by novel filtration strategy in photocatalytic membrane reactors

Abstract

Partially coated TiO2 (pc-TiO2) layer on the porous Al2O3 membrane substrate was developed by using low-cost poly (vinyl chloride) (PVC) to generate interstitial voids to be applied in a photocatalytic membrane reactor for the treatment of organic dye contaminant. The combination of dead-end filtration with cross-flow filtration under intermittent UV irradiation onto a developed composite ceramic membrane was suggested to reduce the membrane fouling effectively. Our study showed that the water flux and anti-fouling properties of the pc-TiO2/Al2O3 composite membrane was much higher than those of uniformly coated TiO2 (uc-TiO2)/Al2O3. Cross-flow membrane filtration provided a much greater synergistic impact on photocatalytic activity for both uc- and pc-TiO2/Al2O3 composite membranes than Al2O3 bare membrane substrate. Less fouling caused by hydrodynamic shear along the membrane surface is thought to be associated with better accessibility of UV irradiation by the reactive surface of the TiO2/Al2O3 composite membrane, promoting the photodegradation of the organic dye contaminant in water filtration.