Lead removal from contaminated marine clay by electrokinetic soil decontamination

This paper reports the remediation of marine clay contaminated with lead by electrokinetics. A series of electrokinetic decontamination experiments including variable conditions such as operating duration, electrical current, concentration of lead and applications of three different chemicals were performed to demonstrate the efficiency of lead removal from natural marine clay sampled in Korea. The experiment results showed that the amounts of hydrogen ions and electroosmotic water flow transported from anode to cathode increased with increasing in the operating duration and the applied electrical current, and with decreasing the initial concentration of lead. The efficiency of heavy metal removal from the contaminated soil was increased with increasing in the operating duration, the applied electrical current and the initial lead concentration. The chemicals used as deprecipitating, complexing and solubilizing agents were efficient in removal of lead from the soil. Here arises a suggestion that injection of such chemicals could be effective in removal of heavy metals from the soil as an auxiliary method in electrokinetic decontamination. (C) 1999 Elsevier Science B.V. All rights reserved.