Operational parameter influence on heavy metal removal from metal plating wastewater by electrocoagulation process

Among the different treatment processes available for industrial wastewater treatment, electrocoagulation represents a challenging option due to several features, such as environmental compatibility, inherent safety, energy and cost effectiveness. The effectiveness of electrocoagulation process (ECP) using aluminium and iron electrodes for the removal of heavy metals from industrial wastewater has been investigated, with particular attention to the effects of operating parameters (pH, inter-electrode distance, hydraulic retention time and current density) on removal efficiency. In the first step of the experimental phase, a laboratory-made artificial wastewater containing heavy metals (Cu, Ni and Pb) was adopted in order to identify the optimum conditions that were subsequently applied to treat a metal plating industrial wastewater. Experimental results revealed that under the optimal experimental conditions (actual pH 6.32, current density 0.026 A cm-2), the removal efficiency of heavy metals from artificial wastewater was higher than 95 %.