Background and Objectives: Electro-Fenton process has been widely applied for dye removal from aqueous solution lately. Fenton's reagent is formed in the electrolysis medium through the simultaneous electrochemical reduction of O₂ and Fe³⁺ to H₂O₂ and Fe²⁺ respectively on the cathode surface. In this paper, COD reduction potential and decolorization of real textile wastewater were evaluated by electrochemically generated Fenton reagent process. This wastewater mainly contains non-biodegradable acidic dyes, which are highly resistant against conventional oxidizing agents.
Materials and Methods: Electro-Fenton process was carried out in an open and undivided cell in order to evaluate the removal of color and COD from real textile wastewater using graphite felt (cathode) and Pt plate (anode) at room temperature. The effects of current density, flow rate of air, electrolysis time, initial pH, and ferrous ion concentration were investigated for real textile wastewater.
Results: The results showed that the optimal experimental conditions obtained in electrochemical studies were as follows: current density=4.8 mA cm-2, pH=3, flow rate of air=1.5L/min, Fe²⁺=3mM and reaction time=160 min. Under these conditions, COD removal and decolorization achieved were 63% and 77.2% respectively.
Conclusion: According to the results achieved, electro-Fenton process can be used as a pretreatment for degradation of colored wastewater and refractory pollutants. Moreover, this feasible technology improves biodegradability of the textile wastewater.