Fenômenos eletrocinéticos em meios porosos, aplicação na remediação de solos: influência do potencial elétrico e do campo elétrico

Abstract

This work shows the results of the behavior of the electric potential and field among two electrodes of a bi-dimensional electrochemical cell built with acrylic with a porous medium distributed uniformly with a solution of a trivalent ion complexed with EDTA. Through an on-line computer aided data acquisition system it was possible to monitor the evolution of the profile of the electric potential within the cell, and, as a result, of the electric field as a function of time, thereby observing the electromigration and the electrofocalization of the ions. This work aims at the theoretical and experimental study of the electromigration of metallic ions, being both a basis for and application to the remediation of soils, through the monitoring of the electric field by observing the focalization, electromigration and electro-osmosis phenomena. The results show that, for the electric fields of 10 and 30 V/cm applied between the electrodes, for a period of 30 minutes, there is the electrofocalization in the region of up to 4cm from the anode in which occurs a pH value favorable to the isoelectric point of the trivalent ion. We also noted that the time of focalization is smaller for a larger electric field applied: 7 minutes for the electric field of 30 V/cm and 17 minutes for a field of 10 V/cm.