Effect of applied voltage on electrokinetic removal of chromium from soils
施加电压对铬污染土壤电动修复的影响

Electrokinetic remediation, variably named as electrochemical soil processing, electromigration, ectrokinetic decontamination or electroreclamation, uses electric currents to extract radionuclides, heavy metals, certain organic compounds, or mixed inorganic species and some organic wastes from soils and slurries. This paper presents the experimental study on the effect of applied voltage on the electrokinetic removal of the chromium from kaolin at laboratory scale. Potassium dichromate was chosen as the pollutant and its initial concentration was 100 mg/kg and 500 mg/kg, the moisture content of samples was 50%. The experiments were operated for 48 hours and the pH of cathode was controlled at 4 -7 with of acetic acid. And a series of voltages were applied. The results indicate that the removal efficiencies increase with the increase of applied voltage, when the voltage is 1 V/cm, the efficiencies increase significantly, the efficiency reach up to 76.7% and 89.8% of two studied samples. The electric energy consumptions also increase significantly due to the increase of applied voltage. The experimental data show that 1 - 1.5 V/cm is effective and costly voltage range for the soils studied.