Removal of chromium Cr(VI) by electroflocculation process with double-aluminum electrode from wastewater

Currently chromium Cr(VI) wastewater treatment by traditional chemical methods have many disadvantages. In this work, the optimized conditions of removal chromium Cr(VI) by the electroflocculation with double-aluminum electrode were investigated. The removal efficiency are mainly influenced by pH value, the current density, the distance between two electrodes, the raw concentration of chromium Cr(VI), the concentration of NaCl, the temperature of the solution and sediment time. It has been found that, when the chromium Cr(VI) ion concentration of wastewater was 20mg/L, the optimal treatment condition were pH of 5.0, the current density of 8 mA/cm², temperature of 25 , the NaCl concentration of 5 mmol, the distance between two electrode of 3cm, the electrolyze time of 1h, the sediment time of of 20min, the removal rate of chromium Cr(VI) can reach 80%.