Rubber wastewater treatment using integrated process ozonation-PSf-sZnO membrane filtration

Natural rubber processing plant produce large volume of wastewater. The application of membrane filtration for treating rubber wastewater faces constraint due to fouling. The incorporation of hydrophilic inorganic nanomaterial into polymeric membrane is developed to improve antifouling properties of membrane. However, this strategy is not effective when treating wastewater with high organic load. In this study, the sulfonated ZnO (sZnO) was embedded into polysulfone (PSf) membrane. In the application, the membrane filtration is coupled with ozonation in sequential processes. The results showed that the morphological structure of fabricated membrane has no defect. The sZnO NPs has good compatibility with PSf polymer. The performance evaluation exhibited that the integrated membrane enhanced the total dissolved solid (TDS), chemical oxygen demand (COD) and N-NH3 removal efficiency up to 18%, 40%, and 92%, respectively. The average permeate flux of the integrated system was also greater than conventional membrane treatment which were 13.3 L.m−2h−1 and 8.8 L.m−2h−1, respectively. The flux decline profile analysis revealed that ozonation process decreased the fouling formation during membrane filtration. This integrated membrane system has great potential on its application for rubber wastewater treatment in large scale.