Electrochemical catalytic degradation and biodegradability enhancement of real textile wastewater by anodic and cathodic reactions

An electro-Fenton process was carried out using undivided cell containing tridimensional graphite felt cathode for treatment of real textile wastewater. The study is essentially focused on effects of pH, applied current and transition metal types (Fe²⁺ and Cu²⁺) as catalysts on the electrochemical degradation efficiency based on color and COD removal and BOD₅/COD value. The results indicated that pH 3 and applied current of 150 mA are the optimum conditions for decolorization and COD removal of real textile wastewater. Moreover, the increasing of the transition metal dosage enhanced efficiency of electro-Fenton process significantly. The BOD₅/COD value of textile wastewater increased from 0.127 to 0.156, 0.38 and 0.453, after electrogenerated hydrogen peroxide with anodic oxidation and electro-Fenton processes conducted with Cu²⁺ and Fe²⁺ respectively. Therefore, biodegradability was significantly enhanced in presence of catalysts (Fe²⁺ and Cu²⁺), particularly in presence of Fe²⁺ which was superior to Cu²⁺. It is also concluded that the electro-Fenton process is an effective technology for the colored wastewater treatment and it can be a pretreatment before biological processes.