ORIGINAL PAPER Evaluation of lead removal from sandy soils using different electrolytes in electrokinetic experiments: prospective for remediation of a real site contaminated with mining wastes B. Murillo-Rivera • I. Gonza ´lez • M. T. Oropeza-Guzman • V. Escobar-Guerrero • E. G. Sumbarda-Ramos • M. M. M. Teutli-Leo ´n Received: 11 September 2009 / Accepted: 11 January 2010 / Published online: 6 February 2010 Ó Springer Science+Business Media B.V. 2010 Abstract The mixture of mining wastes with native soil has similarities with a low permeable porous structure in respect of electrical conductivity and adsorption capacity; therefore, electrokinetics appears as a suitable remediation treatment for sites containing potential toxic elements as Pb, Cd and As. In particular, this paper focuses on the evaluation of the main electrokinetic phenomena that removes Pb(II) from the model sandy soil (98.5% sand and 1.5% clay). For this purpose a study of five different electrolytes, used as moisturizing solution, as well as electrolytes, was done. Results from zeta potential mea- surements and electrokinetic experiments indicate that ammonium acetate and acetic acid were the best electro- lytic solution that ensures the greater Pb removal from sandy soil contaminated with PbCO 3 . Keywords Electrokinetics Á Pb removal Á Zeta potential Á Electroosmotic flow Á Electromigration 1 Introduction In this century, all industries related with explotation and processing of minerals are facing serious environmental problems. Only in Mexico, mining wastes production is estimated to be 123 million tons each year; however, the real status of wastes from mineral processing and their potential impact into the environment are still unclear [1]. As example of a critical case is the one at the mining district of Zimapan in the State of Hidalgo, Mexico, where many tons of mining wastes have been disposed under open sky. This fact has produced a severe contamination of soils and groundwater, which is mainly attributed to the dispersion of weathered accumulated wastes [2]. Reliable studies in the zone have shown that Zimapan’s site presents a high content of potentially toxic elements (PTE) as: arsenic (As), cadmium (Cd), lead (Pb) and zinc (Zn) [2–4]. But, the real danger of these elements depends on their mobility (soluble fraction) and the physico-chemical and mineralogical properties of soil, where PTE could be adsorbed, encapsulated or precipitated with some compo- nents in soil matrix [5]. Under these considerations, application of one or several remediation techniques, it is limited by a critical step of the overall decontamination process. Remediation approaches have considered phytoremediation, mechanical removal as well as addition of carbonates, lime and zeolites to immobilize PTE [6, 7]. Nevertheless, successful of all these procedures has been limited because of the high concen- tration of PTE and expenses involved in large volume transportation and final confinement. At this point, electrokinetic process is an alternative technology that has proven to be able to remove efficiently heavy metals from low permeability soils like sediments, limes and clays [8]. The electrokinetic process has the B. Murillo-Rivera Á I. Gonza ´lez Á V. Escobar-Guerrero Departamento de Quı ´mica, Universidad Auto ´noma Metropolitana Iztapalapa, San Rafael Atlixco 186, Col. Vicentina, 09340 Mexico, D.F., Mexico M. T. Oropeza-Guzman (&) Á E. G. Sumbarda-Ramos Instituto Tecnolo ´gico de Tijuana, Centro de Graduados, Blvd. Industrial sn, Col. Otay, 22500 Tijuana, B.C., Mexico e-mail: oropeza1@yahoo.com M. M. M. Teutli-Leo ´n Facultad de Ingenierı ´a, Benemerita Universidad Autonoma de Puebla, Edificio 123, Ciudad Universitaria, 72570 Puebla, Pue, Mexico 123 J Appl Electrochem (2010) 40:1145–1152 DOI 10.1007/s10800-010-0085-y