A reusable chitosan/TiO2@g-C3N4 nanocomposite membrane for photocatalytic removal of multiple toxic water pollutants under visible light

摘要

Photocatalysis has been proved to be a promising approach in wastewater purification. However, it's hard to recycle powdery photocatalysts from wastewater in the industry, and immobilization of them using materials of larger size can overcome the drawback. Thus, TiO2@g-C3N4 are embedded into chitosan to synthesize a highly reusable and visible-light-driven chitosan/TiO2@g-C3N4 nanocomposite membrane (CTGM) through a facile process in this paper. CTGM performs enhanced photoactivity and the photocatalytic efficiencies of multiple toxic water pollutants are above 90, containing methyl orange (M.O.), rhodamine B (Rh.B), chromium (VI) (Cr (VI)), 2,4-dichlorophenol (2, 4-DCP) and atrazine (ATZ) under visible light at ambient conditions. Significantly, CTGM is easy to be recycled and performs excellent reusability. There isn't any decrease in the photocatalytic decolorization efficiency of Rh.B throughout 10 cycles, and CTGM still keeps the pristine look. Meanwhile, a continuous-flow photocatalysis system is set up and 90 of Rh.B can be effectively decolorized. In general, a simple approach is developed to prepare a novel, effective and visible-light-driven membrane with easiness to reuse, and a feasible photocatalysis continuous-flow system is designed to be a reference to wastewater treatment in the industry.