Photocatalytic degradation of Milling Yellow dye using sol–gel synthesized CeO 2

Abstract The photocatalytic degradation of Xylene Milling Yellow 6 G in aqueous solutions under UV exposure was studied with sol–gel synthesized CeO 2 catalyst. The effects of catalyst loading, initial dye concentration, pH and temperature were studied and the optimum values for maximum degradation were determined. Using a 125 W high pressure mercury lamp, an optimum degradation of 10 ppm dye solution was observed with 1 g/L catalyst. Initial dye concentration exhibited a significant negative effect on photocatalytic degradation. With 1 g/L catalyst, natural pH of the solution, ambient temperature, and initial dye concentration of 10 ppm, complete degradation was achieved within 30 min of UV exposure. The sol–gel synthesized catalyst showed better photocatalytic activity than combustion synthesized as well as commercial catalysts. A degradation mechanism was proposed based on the degradation products identified by LC–MS.