Construction of CuO@CuS/PVDF composite membrane and its superiority for degradation of antibiotics by activation of persulfate

Antibiotics were frequently detected in influent of wastewater treatment plants (WTPs), which brought potential crisis to human beings and the environment. In this study, series of CuO@CuS nanocomposites were synthesized by co-precipitation combined with microwave treatment, which was employed to activate persulfate (PS) toward degrading tetracycline (TC). Results indicated that CuO@CuS with a molar ratio of 2:1 displayed the superior PS activation performance with TC removal efficiency. In order to further improve the recycle and utilization of nano-composites, CuO@CuS/PVDF membrane were constructed, leading to a greatly enhancement of TC removal efficiency (87.4%) within 3 h. Subsequently, physicochemical properties of CuO@CuS/PVDF membrane were characterized systematically. The effects of operating parameters, such as PS concentration, the initial pH value and co-existing ion on the CuO@CuS/PVDF-PS system were optimized in detail. The analysis results disclosed that when [PS] = 0.4 g/L, pH = 3, the system exhibited excellent degradation efficiency by elimination of contaminant solution. Furthermore, the enhanced mechanism of CuO@CuS/PVDF-PS system for organic pollutants elimination was proposed and confirmed, which was ascribed to the involvement of hydroxyl radical (center dot OH), sulfate radical (SO4 center dot-;) and singlet oxygen (O-1(2)). Thence, the constructed membrane/PS system exhibited potential application in wastewater treatment.

Automated summary

In this study, CuO@CuS nanocomposites were successfully synthesized and a CuO@CuS/PVDF membrane was constructed to effectively degrade tetracycline with a removal efficiency of 87.4%. The system was optimized for operating parameters and a mechanism involving hydroxyl radicals, sulfate radicals, and singlet oxygen was proposed for organic pollutants elimination. These findings suggest the potential application of the membrane/PS system in wastewater treatment.