Optimization for the photocatalytic degradation of methylene blue using Sol-gel Derived TiO2 photocatalyst supported on montmorillonite

Abstract

Photocatalytic is a method that can be used to replace conventional wastewater treatment to treat dyes in industry. Photocatalytic degradation of methylene blue (MB) required titanium dioxide (TiO2) photocatalyst under UV radiation. Immobilized TiO2 photocatalyst into support is a solution for easy recovery of photocatalyst after photocatalytic process. Sol-gel method was used to prepare immobilized TiO2 photocatalyst into montmorillonite. The surface morphology of photocatalyst developed has been studied using Scanning Electron Microscope (SEM) where the result indicated that the immobilization was a success. Increasing the amount of montmorillonite used can increase the immbolized amount of TiO2 photocatalyst. The photocatalytic equipment was successfully conducted under UV radiation in a closed box. The photocatalytic degradation was studied by considering three parameters which are photocatalyst loading, initial concentration of MB and pH of solution. Interaction of all three parameters on photocatalytic degradation of methylene was investigated using Design of Expert (DOE) software together with Response Surface Methodology (RSM). The optimum condition found was to be at 40.94 ppm initial concentration of methylene blue with 0.69 g/L photocatalyst loading and pH of 3.13.