Glass coated-nanostructure semiconductor TiO2/RGO/MoS2 for dye removal and disinfection of wastewater: Design and construction of a novel fixed-bed photocatalytic reactor

Abstract

In the field of applied semiconductor, TiO2/RGO/MoS2 nanocomposite as a high performance photocatalyst has been synthesized. Prepared semiconductor has been coated on borosilicate glass rods with a facile one pot process and imbedded in the photoreactor chamber. Fabrication and presentation of an appropriate photoreactor for effective wastewater treatment has been developed. In this photoreactor continuous air by producing bubbles provides an effective mixing of the target solution. The performance of the designated system has been examined by investing the photocatalytic degradation of rhodamine B (RhB) and was more than 95% dye removal. Electrochemical investigation (Mott-Schottky, Nyquist and Bode plots) showed that long electron lifetime of TiO2/RGO/MoS2 is the main reason for high photoactivity of this nanocomposite. Optimization of the different parameters such as influence of bubbling and light intensity of the photoreactor, the initial pH and the initial concentration of RhB on the photocatalytic performance have been also studied. TOC of the reaction were conducted which showed good mineralization. The photocatalyst powder was characterized by BET, BJH, SEM, EDX, FT-IR, XRD, EIS, and ICP-OES. Low leaching has been confirmed by ICP investigation. Photocatalytic treatment of liquorice factory wastewater in several concentrations has been also studied. Disinfection capability of TiO2/RGO/MoS2, in designated system for liquorice factory wastewater has been investigated. This system is so effective to eliminate harmful microorganisms. Total coliform for liquorice factory wastewater with a 21000 MPN/100 before treatment reached to zero MPN/100 after treatment in optimum reaction conditions.