Electrokinetic remediation of lead‐, zinc‐ and cadmium‐contaminated soil

Abstract

Electrokinetic remediation of lead-, zinc-and cadmium-contaminated sand and clayey soils has been investigated under laboratory-scale conditions. Soil extracts of heavy metals (by 1 M HCl solution) were analysed by optical emission spectrometry. The ef®ciency of electrochemical remediation was partially dependent on the pH of the soil media. With pH increase, the migration of heavy metal ions toward the cathode was limited. When acetic acid was added to the sandy soil, almost complete remediation was achieved. A clay layer inserted in the cathode area did enhance the remediation rate. The most effective clean-up was achieved for zinc and cadmium, with less effective clean-up being achieved for lead. The effectiveness of the electrokinetic remediation of heavy metalcontaminated clayey soil was low. The appropriate acidity was not achieved using acetic acid because of the high buffering capacity of clay, and metal ion migration was impeded by its sorption onto some clay components. The conclusion was made that clays could be used as immobilizing media for heavy metal ions by electrokinetic remediation of various soils.

Application of sequential extraction analysis to electrokinetic remediation of cadmium, nickel and zinc from contaminated soils

“…In addition, slight differences can be observed between the distribution of Cd and Zn for all three experiments. The mobility of Cd and Zn through the soil followed the same pattern [29]. These findings are consistent with previous studies conducted in lab-scale electrokinetic experiments with chelate agents conditioning the cathode compartment.…”

Electrokinetic remediation of wood preservative contaminated soil containing copper, chromium, and arsenic

“…Although, most of the investigations were done on soils contaminated with single metallic species [4][5][6][7][8][9][11][12][13][14][15][16][17][18][19][20][21]26,38], limited tests have been done on soils contaminated with multiple metallic species [10,[22][23][24][25][27][28][29][30][31][32][33][34][35][36][37]. Previous tests conducted on soils contaminated with multiple species have shown that, the presence of multiple metals had an impact on the removal efficiencies [34].…”

Washing enhanced electrokinetic remediation for removal cadmium from real contaminated soil

“…The electrokinetic process is a great promise for remediation of polluted soils, as it has high removal efficiency and time effectiveness in low permeability soils [6]. Electrokinetic remediation can be used to treat soils contaminated with inorganic species [7][8][9][10][11][12][13], organic compounds [14][15][16] and radionuclides [17,18].…”