Feasibility of Cr (VI) Removal from Aqueous Solution Using Electrochemical Bipolar Aluminum Electrodes

Document Type : Technical Note



Electrocoagulation is one of the technologies which have been considered by many researchers in recent years. This process has many advantages including high efficiency, no need to chemical addition, low sludge production, capability of process control, easy to operation and maintenance. Bipolar electrodes system is one of the electrocoagulation techniques which can be used for increasing the process efficiency and better distribution of the electric current. The aim of this study was to remove hexavalent chromium from aqueous solution by electrocoagulation technique. Response surface methodology (RSM) was used to optimize the parameters involving in the process, and the effect of current density, initial chromium concentration and pH on the process were investigated. At optimal conditions, for the highest chromium removal (>90%), the optimum initial chromium, reaction time, current density and pH were found to be 117 mg/L, 50 min, 11.75 mA cm-2 and 4.5, respectively. It can be stated that electrocoagulation is an efficient technique for separation and removing high chromium concentration from aqueous solutions.


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