A highly durable and hydrophilic PVDF- MoS2/WO3-PVA membrane with visible light driven self-cleaning performance for pollutant-burdened natural rubber wastewater treatment

Recently, the unification of photocatalytic degradation and hydrophilic properties has received a remarkable attention in membrane-based operation. In this study, the PVDF membrane was tailored by the incorporation of MoS2/WO3 recognized as MSW photocatalyst material with a cross-linked PVA. The filtration process was conducted with and without visible-light irradiation, and the properties of the clean and fouled membrane were identified using a scanning electron microscope (SEM), infrared spectroscopy (FTIR), and X-ray diffraction (XRD) analysis. The characterization results confirmed the successful blending of the composite material in the PVDF membrane. The PVDF-MSW-PVA membrane exhibited convincing performances with a high-photodegradation efficiency and excellent self-cleaning ability. The PVDF-MSW-PVA membrane achieved an initial flux of 100.66 L.m- 2.h-1 and exhibited 98.77 % of chemical oxygen demand (COD), 94.30 % of total dissolved solid (TDS), and 96.66 % of ammonia nitrogen (NH3-N) rejection under visible-light illumination. The excellent antifouling and self-cleaning ability of the membrane was confirmed by the unnoticeable decrease of permeate flux after 5 cycle photo-filtration process, the highest flux recovery ratio of 96.93 %, and a decrease of total fouling retention of the membrane with the higher Rr than that of Rir. The modified membrane also demonstrated good reusability for long term-used upon 10 h of usage for the filtration process under visible-light irradiation. These results suggest the synergetic use of photocatalytic and hydrophilic material for the treatment of pollutantburdened natural rubber wastewater via a combined degradation and filtration process.

Automated summary

In this study, a PVDF membrane was modified with MoS2/WO3 nanocomposite and cross-linked PVA, achieving the integration of photocatalytic degradation and hydrophilic properties. The modified membrane showed high photocatalytic efficiency and excellent self-cleaning ability under visible-light illumination, achieving efficient removal of COD, TDS, and ammonia nitrogen. The membrane also demonstrated good reusability and high flux recovery ratio. This study highlights the synergistic use of photocatalytic and hydrophilic materials for the treatment of pollutant-burdened wastewater.