Decolorization of peach red azo dye, HF6 by Fenton reaction: Initial rate analysis

The wastewater containing non-biodegradable and toxic substances from textile industries is an important source of environmental contamination. In addition to the traditional secondary treatment, tertiary treatment such as advanced oxidation process is used to treat dye-containing wastewater. Fenton reaction is one of the most popular advanced oxidation processes to degrade dyestuffs in water into carbon dioxide, water, and other harmless products. In this study, a series of dye degradation experiments by the Fenton reagent were conducted inside an UV cell to allow directly measuring dye degradation kinetics. The initial dye degradation rates at varying initial H2O2, Fe2+, and dye concentrations were measured. A rate equation for dye degradation, derived from the reaction mechanism that reflects the involved elementary reaction steps, fit the experimental kinetic data satisfactorily and thus can be used for reactor design.