Enhanced Electrokinetic Remediation of Cadmium Contaminated Soil

Abstract

In an attempt to remediate contaminated soil, a new technique of purging cadmium from soil is examined by enhanced electrokinetic method. It involves the passage of low level direct current between two electrodes in the soil to remove contaminant. An apparatus consisting of four principal parts; soil cell, electrode compartments, electrolyte solution reservoir and power supply unit, was designed and constructed. A 2 kg sample of clay soil with background cadmium concentration of 0.08 mg/kg, was artificially contaminated to the tone of 38.45 mg/kg as its cadmium concentration and then treated in the electrokinetic apparatus over a period of 2 days. Samples were collected from 4 points from the soil at intervals of 3cm from the anode electrode and analyzed for cadmium. Results indicate a 76.2%, 52.3%, 42.4%, 18.16% removal efficiency of cadmium from respective distances of 3cm, 6cm, 8cm and 12cm from the anode. The enhanced electrokinetic soil remediation technique is an emerging technology for treating both polar and non-polar contaminants in soils, with promising prospects as a soil remediation process as it has high
removal efficiency and time effectiveness.