Reducing Agents Enhanced Electrokinetic Soil Remediation (EKSR) for Heavy Metal Contaminated Soil

Document Type: Research Article


1 Department of Biotechnology, Koneru Lakshmaiah Education Foundation, Vaddeswaram-522502, A.P, INDIA

2 School of Advanced Sciences (SAS), Department of Chemistry, VIT University, Vellore-632014, INDIA


Reducing agents-Enhanced electrokinetic Soil Remediation (EKSR) was performed for the removal of chromium (Cr), cobalt (Co) and nickel (Ni) from contaminated soil. The reducing agents oxalic acid and ascorbic acid were investigated under constant voltage gradient (2.0 V/cm), current changes, pH, redox potential, concentration changes and removal performance of Heavy Metals (HMs). The results indicated that the reducing agents were effective in the desorption of metals at the cathode with catholyte conditioning pH. The removal performance of heavy metals in reducing agents-enhanced EKSR was about 2-2.5 times more than in unenhanced treatment. The amount of HMs migrated to the catholyte was more than in the anolyte, which might be evidenced that the negatively charged metal-oxalate/ascorbate complexes migrated via electroosmosis. However, positively charged HM-oxalate/ascorbate complexes and free HM cations moved to the catholyte by electromigration action. Furthermore, the mass balance and cost analysis
were performed for all EKSR experiments after 20 days of operation. The energy consumption per cubic meter of treated soil was 1104-18496 kWh/m3 and the total cost was about US$ 110.4-2095, including the cost of the enhancing agents. The study demonstrated that reducing agents-enhanced EKSR is cost-effective and efficient in the removal of HMs from contaminated soil.


Main Subjects

[1] Devolder P.S., Brown S.L., Hesterberg D., Pandya K., Metal Bioavailability and Speciation in a Wetland Tailings Repository Amended with Biosolids Compost, Wood Ash, and Sulfate, J. Environ. Qual., 32(3): 851–864 (2003).

[2] Hashim M.A., Mukhopadhyay S., Sahu J.N., Sengupta B., Remediation Technologies for Heavy Metal Contaminated Groundwater, J. Environ. Manage., 92(10): 2355–2388 (2011).

[3] Brown G.A., Comparative Evaluation of NTA and EDTA for Extractive Decontamination of pb-Polluted Soils, Water, Air and Soil Pollotion., 45: 361–369 (1989).

[4]    Lim T., Tay J., Wang J., Chelating-Agent-Enhanced Heavy Metal Extraction from a Contaminated Acidic Soil, J.Env. Engg., 130: 59–66 (2004).

[5]    Kim J., Lee Y., Chung J., The Role of Organic Acids in the Mobilization of Heavy Metals from Soil, KSCE J. Civil. Engg., 17(7): 1596–1602 (2013).

[6]    Oustan S., Neyshabouri M.R., Reyhanitabar A., Mobilisation of Heavy Metals from a Contaminated Calcareous Soil Using Organic Acids, Malaysian J. of Soil Sci., 19, 141–155 (2015).

[7]    Oustan S., Heidari S., Neyshabouri M.R., Reyhanitabar A., Bybordi A., Removal of Heavy Metals from a Contaminated Calcareous Soil using Oxalic and Acetic Acids as Chelating Agents, I. Con. Env. Engg., 8, 152–155 (2011).

[8]    Han J.G., Hong K.K., Kim Y.W., Lee J.Y., Enhanced Electrokinetic (E/K) Remediation on Copper Contaminated Soil by CFW (Carbonized Foods Waste), J. Hazard. Mater., 177: 530–538 (2010).

[9] Sivapullaiah P.V., Nagendra Prakash B.S., Suma B.N., Electrokinetic Removal of Heavy Metals from Soil, J. Electrochem. Sci. Eng., 5: 47–65 (2015).

[10] Amrate S., Akretche D.E., Innocent C., Seta P., Removal of Pb from a Calcareous Soil During EDTA-Enhanced Electrokinetic Extraction, Sci. Total Environ., 349: 56–66 (2005).

[11] Traina G., Morselli L., Adorno G.P., Electrokinetic Remediation of Bottom Ash from Municipal Solid Waste Incinerator, Electrochim. Acta., 52:3380–3385 (2007).

[12] Pazos M., Plaza A., Martín M., Lobo M.C., The Impact of Electrokinetic Treatment on a Loamy-Sand Soil Properties, Chem. Eng. J., 183: 231–237 (2012).

[13]  Reddy K.R., Electrokinetic Remediation of Soils at Complex Contaminated Sites, Coupled Phenom. Environ. Geotech., 131–147 (2013).

[14] Alshawabkeh B.A.N., Yeung A.T., Bricka M.R., Practical Aspects of in-S Itu Electrokinetic Extraction, J. Environ. Eng., 27–36 (1999).

[15] Hamdan S.H., Molelekwa G.F., Van der Brugge, B., Electrokinetic Remediation Technique: An Integrated Approach to Finding New Strategies for Restoration of Saline Soil and to Control Seawater Intrusion, Chem. Electro. Chem., 1: 1104–1117 (2014).

[16] Srivastava R.K., Tiwari, R.P., Ramudu P.B., Electrokinetic Remediation Study for Cadmium Contaminated SoilIran. J. Environ. Health. Sci. Eng., 4(4): 207–214 (2007).

[17] Li Z.M., Yu J.W N.I., Electroremediation: Removal of Heavy Metals from Soil by Using Cation Selective Membrance, Envionmental Sci. Technol., 32: 394–397 (1998).

[19] Lee H.H., Yang J.W., A New Method to Control Electrolytes pH by Circulation System in Electrokinetic Soil Remediation, J. Hazard. Mater.,77: 227–240 (2000).

[20] Wang J.Y., Zhang D.S., Stabnikova O., Tay J.H., Evaluation of Electrokinetic Removal of Heavy Metals from Sewage Sludge, J. Hazard. Mater., 124:139–146 (2005).

[21] Liu Y., Chen J., Cai Z., Chen R., Sun Q., Sun M., Removal of Copper and Nickel from Municipal Sludge Using an Improved Electrokinetic Process, Chem. Eng. J., 307: 1008–1016 (2017).

[22] Sierra C., Martínez J., Menéndez-Aguado J.M., Afif E., Gallego J.R.,  High Intensity Magnetic Separation for the Clean-up of a Site Polluted by Lead Metallurgy, J. Hazard. Mater., 248: 194–201 (2013).

[23] Lockwood C.L., Mortimer R.J.G., Stewart D.I., Mayes W.M., Peacock C.L., Polya D.A., Lythgoe P.R., Lehoux A.P., Gruiz K., Burke I.T., Mobilisation of Arsenic from Bauxite Residue (Red Mud) Affected Soils: Effect of pH and Redox Conditions, Appl. Geochemistry., 51: 268–277 (2014).

[24] Sanderson P., Naidu R., Bolan N., Lim J.E., Ok Y.S., Chemical Stabilisation of Lead in Shooting Range Soils with Phosphate and Magnesium Oxide: Synchrotron Investigation, J. Hazard. Mater., 299:395–403 (2015).

[26] Reddy K.R., Chinthamreddy S., Synergistic Effects of Multiple Electrokinetic Remediation of Soils, Remediation Journal., 11(3): 85–109 (2001).

[27] Reddy K.R., Chinthamreddy S., Sequentially Enhanced Electrokinetic Remediation of Heavy Metals in Low Buffering Clayey Soils, J. Geotech. Geoenvironmental Eng., 129: 263–277 (2003).

[29] Yeung A.T., Gu Y.Y.,  A Review on Techniques to Enhance Electrochemical Remediation of Contaminated Soils, J. Hazard. Mater., 195: 11–29 (2011).

[31] Sasaki K., Haga T., Hirajima T., Kurosawa K., Tsunekawa M., Distribution and Transition of Heavy Metals in Mine Tailing Dumps, Material Transactions, 43:2778–2783 (2002).

[33] Tang W.W., Zeng G.M., Gong J.L., Liang J., Xu P., Zhang C., Huang B.Bin.,  Impact of Humic/Fulvic Acid on the Removal of Heavy Metals from Aqueous Solutions Using Nanomaterials: A Review, Sci. Total Environ. 468: 1014–1027 (2014).

[34] Bahemmat M., Farahbakhsh M., Kianirad M.,  Humic Substances-Enhanced Electroremediation of Heavy Metals Contaminated Soil, J. Hazard. Mater., 312: 307–318 (2016).

[35] Ma J.W., Wang F.Y., Huang Z.H., Wang H., Simultaneous Removal of 2,4-dichlorophenol and Cd from Soils by Electrokinetic Remediation Combined with Activated Bamboo Charcoal, J. Hazard. Mater., 176: 715–720 (2010).

[36] Pedersen K.B., Kirkelund G.M., Ottosen L.M., Jensen P.E., Lejon T., Multivariate Methods for Evaluating the Efficiency of Electrodialytic Removal of Heavy Metals from Polluted Harbour Sediments, J. Hazard. Mater., 283: 712–720 (2015).

[37] Giannis A., Pentari D., Wang J.Y., Gidarakos E.,  Application of Sequential Extraction Analysis to Electrokinetic Remediation of Cadmium, Nickel and Zinc from Contaminated Soils, J. Hazard. Mater., 184: 547–554 (2010).

[38] Yeung A.T., Hsu C., Menon R.M., EDTA-Enhanced Electrokinetic Extraction of Lead, J. Geotech. Eng., 122: 666–673 (1996).