Optimization of parameters of electrocoagulation/flotation process for removal of Acid Red 14 with mesh stainless steel electrodes

Abstract

Abstract Dyes are persistent compounds that are not easily biodegraded and are considered as carcinogenic. Electro-coagulation and electro-flotation method, due to its adaptability and compatibility with the environment, is regarded as one of the appropriate methods for the treatment of industrial wastewater containing dye. In this study in which stainless steel mesh electrodes with a horizontal arrangement are used, the most important parameters affecting the performance of the simultaneous system of electro-coagulation and electro-flotation, including electrodes area, of distance between electrodes, electrical conductivity of the solution, type of electrolyte, and initial pH were examined. The effect of every one of these parameters in color removal efficiency of Acid Red 14 from artificial wastewater, energy consumption and anode was determined and their values were optimized. The area of the electrode equals 20.5 cm2, the distance between the electrodes is 0.5 cm, electrical conductivity 3,600 μS/cm, and initial pH 7 were selected as the optimum values, and dye removal efficiency of 99% with initial concentration of 150 mg/L and electric current density 40 mA/cm2 (0.8 A) were obtained under optimum conditions and within 20 minutes. The advantages of this method are low energy and material consumption, and low sludge production.