Preparation and characterization of photocatalytic PSf-TiO₂/GO nanohybrid membrane for the degradation of organic contaminants in natural rubber wastewater

Although the improvement of photocatalytic property has been reported to be a promising strategy to enhance the anti-fouling of the membranes, the inclusion of a single photocatalytic material into membrane matrix still exhibits low organic foulants degradation capacity. In this study, two photoactive materials, i.e. nano-TiO2 and graphene oxide (GO) are selected as fillers in the fabrication of polysulfone (PSf) membranes. A thorough investigation was devoted to the photocatalytic activity of the membrane for the degradation of organic pollutants in natural rubber wastewater under dark environment and static UV light irradiation. In order to search the best TiO2 and GO composition, early data curation based on membrane permeability and selectivity was carried out. Membrane with TiO2 loading at 1.5 wt% demonstrated its best performance by providing permeate flux of 16.29 L m-2 h-1 with organic removal up to 79.27%. On the other hand, the membrane loaded with 1.0 wt% GO only exhibited permeate flux up to 8.15 L m-2 h-1 with organic removal up to 70.73%. Upon the incorporation of TiO2/GO mixture as filler materials to the PSf membrane, remarkable results were achieved, which consists of permeate flux, organic and ammonia removals of 13.05 L m-2 h-1, 60.98% and 91.27%, respectively. Based on batch photocatalytic activity assessment, the PSf-TiO2/GO membrane showed the fastest photodegradation reaction. The results proved that the incorporation of TiO2 and GO nano particle as photoactive materials to the PSf membrane matrix results in a synergistic effect in improving photocatalytic capacity and stability of the membrane.