Advanced oxidation processes of Mordant Violet 40 dye in freshwater and seawater

Abstract

This paper examines the possibility of applying ozone (O3) and O3 combined with ultraviolet (UV) to degrade the content of synthetic wastewater Mordant Violet 40 dye (MV-40). The experimental parameters included pH, initial dye concentration and time of reaction; all were assessed in a batch reactor to achieve the optimum operating circumstances. The results obtained showed that the pH and initial MV-40 dye concentration controlled the decolorization process. The maximum decolorization of MV-40 dye solution was obtained at pH 9. More than 98% of color removal was obtained within 20 min for both UV assisted O3 and individual O3 treatment of 100 ppm dye concentration. Kinetic analyses showed that the decolorization of MV-40 dye followed the second-order kinetics. The degree of decolorization of MV-40 dye solution was indirectly proportional to the initial dye concentration. Gas Chromatography Mass Spectrum analysis of treated synthetic dye solution was performed at the end of the pre-treatment time to the final degradation products of MV-40 dye. The obtained results explained that the advanced oxidation processes enhanced the biodegradability and lowered the zooplankton toxicity of the treated MV-40 dye solution.