Photocatalytic Degradation of Monoazo Dye in Ethanol using Zinc Oxide in Ultra-Violet Radiation

Abstract

The photocatalytic degradation of azo dye 2-(2-naphthyl azo)-4,5-diphenyl imidazole was studied. Solutions of different concentrations of this dye using zinc oxide under UV irradiation. Different parameters were measured such as the catalyst amount, dye concentrations, light intensity and effect of pH. The optimum concentration of catalyst was 0.15 g/100 mL while the optimum concentration of dye was 50 ppm. It has been shown that the best pH to degrade monoazo dye 8.1 with 8.44 mW/cm 2 light intensity. The photocatalytic degradation of azo dye follows the first order reaction. In addition, photocatalytic degradation of the dye has been studied using different concentrations of aluminium oxide suspended in an aqueous solution of this dye irradiated by ultraviolet lamp in a vessel reactor at room temperature, with 10 cm 3 /min air bubble has been passed through the solution. In addition, when the dye concentration increased, the photocatalytic degradation efficiency of dye decreased to 83.54 %.