Influence of Operational Parameters on the Decolorization of an Azo Reactive Dye (C.I. Reactive Red 120) by Fenton Process

This study provides information on the application of the Fenton process as an advanced oxidation method for the treatment of wastewater containing an azo reactive dye (C.I. Reactive Red 120). To establish cost-efficient operating conditions for potential application of Fenton oxidation process, the influence of the main operating parameters such as iron sulfate and hydrogen peroxide doses, solution pH, temperature, initial dye concentration and presence different concentrations of sodium chloride and sodium sulfate have been studied systematically in a laboratory scale. The obtained results showed that the best pH value for decolorization of dye solution was 3. The decolorization of RR120 enhanced with the increasing of reaction temperature but decreased as a presence of chloride and sulfate ions. The increase of Fe2+ and H2O2 doses accelerated the color and COD removals until a point where further addition of Fe2+ or H2O2 became inefficient and unnecessary. The result indicated that over 99% color removal and up to 74% COD removal can be obtained by Fenton’s oxidation.