Decolorization by ozone of direct dyes in presence of some catalysts

Abstract Decolorization of two direct dyes by ozone in aqueous medium was studied in absence and in presence of some salts at room temperature. It was found that zinc sulfate catalyses the process of decolorization. Equations to describe the process and to allow prediction of ozone requirement were developed. The new findings of this study would have an impact on wastewater treatment techniques using ozone.