Removal of tetracycline hydrochloride using S–g-C3N4/PTFE membrane under visible light irradiation

As a type of medicine, tetracycline (TC) is widely used in the world, but it is not easy to degrade due to its poor biochemical properties and stable physicochemical properties. In this work, graphite sulfide carbon nitride compound (S–g-C3N4/PTFE membrane) photocatalyst, formed from a PTFE membrane and graphite sulfide carbon nitride (S–g-C3N4), was prepared for the treatment of TC in wastewater. A variety of characterization methods were used to analyze the catalyst, such as scanning electron microscope (SEM), X-ray diffractometer (XRD), infrared spectrometer (FTIR), X-ray photoelectron spectroscopy (XPS), etc. Photocatalytic experiments showed that the photocatalytic degradation extent was 98.1% when the catalyst dosage was 1 ​g/L, the loading of S–g-C3N4 was 50 ​mg, pH was 5 and the initial concentration of TC was 10 ​mg/L. Moreover, S–g-C3N4/PTFE membrane has good recovery performance and photocatalytic stability, and has good degradation performance for most pollutants in urban sewage treatment plants. S–g-C3N4/PTFE membrane will have good application prospects in contaminated water environments because of its advantages of excellent degradation ability, easy regeneration and separation from the water phase. •Doping S into g-C3N4 reduces the band gap and enhances the photocatalysis ability under visible light•Loading photocatalyst onto PTFE membrane improves the recyclability of the powder photocatalyst.•The S-g-C3N4/PTFE was used to treat wastewater contaminated by antibiotics•The degradation effect and degradation mechanism of the composite material on tetracycline in water were studied.