Effect of Applied Electrical Field and the Initial Soil Concentration on Species Recovery During Application of the Electroremediation Process

Abstract

E lectrokinetic phenomena can be employed for a soil decontamination process generally called electroremediation. The ionic species in solution migrate through a porous medium essentially by electro-osmosis and electromigration. The aim of this work was to contribute to knowledge of this process by studying the effect of some operating conditions on the species recovery through an experimental program. The in uence of the electrical eld applied to the medium and the initial concentration of the soil solution, in particular, are studied. First, the electrokinetic transport phenomena are presented. Then, the experimental setup and procedures carried out are described. The setup consists of a speci c electroremediation cell containing a Na-doped kaolinite medium. Chemical reactions were limited by using the sodium as a tracer. The experimental results show the important coupling existing between solution concentration and the electrical current and their in uence on both the amount and the rate of transported mass. Moreover, the dependence of the electro-osmotic coef cient on the electrical eld applied was demonstrated. The in uence of the solution concentration on the electro-osmosis is not obvious, probably due to the light modi cation of the zeta potential for the system studied.

Contaminant Extractability by Electrokinetics

“…Therefore, the electric field strength also increases linearly with distance towards the cathode. The effect of current density on electrokinetic extraction was studied by Hamed and Bhadra (1997) and Pomès et al (2002). Their experimental results indicated electro-osmotic fluid volume flow rate increased with current den-212 YEUNG sity, resulting in a considerable reduction in processing time.…”

Correlation of the Physicochemical Properties in Soils from Tenerife Island, Measuring the Electric Current in an Electrokinetic Experiment

“…Entre estas magnitudes, la corriente de electrólisis, cuando se trabaja a potencial aplicado constante, es una de las reportadas habitualmente en la literatura científica [1][2][3][4][5][6][7][8][9][10][11][12]. Entre otros, podemos destacar estudios encaminados a la eliminación de metales pesados tales como Pb, Cd, Cr, Ni, Cu y Zn [1,5,7,[8][9][10][11][12], en los que la corriente † Dedicado a la Dra. …”