Electrokinetic Remediation of Metal‐Contaminated Field Soil

Abstract

Abstract This study evaluates the electrokinetic remediation of a low permeability field soil contaminated with heavy metals. The soil was contaminated with a wide range of heavy metals; but, in order to simulate the actual source zone contamination, the soil was also spiked with lead and mercury at 1000 mg/Kg each. Four bench‐scale electrokinetic experiments were conducted at a voltage gradient of 2.0 VDC/cm and a hydraulic gradient of 1.4 using four different extracting solutions, namely 0.2 M ethylenediamine tetra acetic acid (EDTA), 0.2 M diethylene triamine penta acetic acid (DTPA), 0.2 M potassium iodide (KI), and 10% hydroxypropyl‐β‐cyclodextrin (HPCD). EDTA and KI were found to be efficient in the removal of lead and mercury, respectively. On the mass‐efficiency basis, the EDTA‐enhanced system is found to be more effective for the simultaneous removal of a variety of metals, while KI was found to be effective for the selective removal of mercury from the field soil.