Optimizing Electrochemical Parameters for Enhanced Heavy Metal and Organic Matter Removal by Electrocoagulation- lectrofloculation Reactors-A Comparative Study

Industrial effluents laden with heavy metals and organic matter necessitate diligent treatment, owing to their pronounced threat to both biota and human populations, attributed to their enduring persistence, inherent toxicity, and proclivity for bioaccumulation. This investigation centers on the eradication of copper, nickel, and humic acid (HA) through the utilization of the electrocoagulation- electrofloculation process (EC-EF) employing aluminum electrodes. In an endeavor to enhance the efficacy of the EC process, a comprehensive examination of various EC parameters including solution pH, current density (J), electrolyte concentration, and connection mode was conducted. Optimal outcomes, characterized by minimal residual concentrations and diminished energy consumption, were achieved under specific conditions: pH 5 for Cu and Ni, pH 4 for HA, current density of 1.388 mA cm-2, electrolyte concentration of 1 g L-1 for Cu, 1.5 g L-1 for Ni, and 0.15 g L-1 for HA, with monopolar connection mode. Under these optimized parameters, complete HA elimination and notably low residual concentrations of Cu (0.4 mg L-1) and Ni (2.354 mg L-1) were attained, translating to elimination rates of 100%, 99%, and 94.65% for HA, Cu, and Ni, respectively, from industrial wastewater. This accomplishment was realized within modest electrolysis duration of 20 min, with a commendably low energy consumption of 0.04 kW.m-3. The demonstrated 100% elimination rate of HA underscores the superior efficacy of EC in organic matter removal when compared to its efficacy in heavy metal removal. These compelling results posit EC as a cost-effective and viable technique for the treatment of industrial wastewater.