Pulsed-Electro-Fenton method: Experiments were conducted on the direct and pulsed current-electro-Fenton processes. EAOP methods were compared for elimination color and COD from industrial wastewater. EF technique effectively removes color and COD while consuming minimal electricity. Operating parameters were evaluated to improve process efficiency.

Abstract

In recent years, there has been a rise in the use of electrochemical and advanced oxidation methods to treat the industrial wastewater. The efficiency of several approaches for treating industrial wastewater, including hydrogen peroxide (H₂O₂), electro–Fenton (EF) and pulsed–electro–Fenton (PEF) processes were all investigated. In evaluation to the H₂O₂, EF, and PEF technologies, the results showed that the PEF process produced 100 % total color and 98 % chemcial oxygen demand (COD) removal efficiency with a low consumption of power of 3.4 kWhrm⁻³. The experimental parameters comprised the following: COD – 2500 mg L⁻¹, pH – 3, H₂O₂ – 300 mg L⁻¹, distance between electrode – 0.75 cm, current – 0.40 A, cycle of pulse duty – 0.75, combination of electrode – Fe/Fe, stirring speed – 500 rpm and treatment duration (TD) – 125 min. It was demonstrated that increasing the TD, current, and H₂O₂ while lowering the COD content improved the COD elimination efficiency while employing a iron (Fe/Fe) electrode combination with wastewater pH of 3. The efficiency of the EF process has been reduced in comparison to the PEF process because of the development of an impermeable oxide layer on the cathode and the oxidation–induced corrosion on the anode. Consequently, experimental results have indicated that the PEF could be a more promising technology than the EF method for eliminating pollutants from wastewater with reduced power consumption and process efficiency.