Aplicação da técnica eletrocinética na remediação de areia contaminada com íons Pb utilizando eletrodos de Fe e aço inox

Abstract

An electrokinetic reactor (EK-reactor) applied to the remediation of the contaminated sand with Pb ions was developed and studied. Thus, a lab-scale EK-reactor equipped with different electrodes iron (5 x 6 x 0.275 cm) and stainless steel (5 x 6 x 0.091 cm), being the effective area 65 cm 2 e 62 cm 2 , respectively; immersed on the tank contained electrolytic solution, was used. Between the tank, another compartments contained simulated contaminated sand by the solution of 4000 mg Pb L -1 , and equipped with four collection drains, was developed. Using 15.4 mA cm -2 e 16.1 mA cm -2 for experiments with iron and stainless steel electrodes, respectively; and collected samples in different EK-times on the drains and tank, the Pb ions reduction as well as recuperation on the sand and tank, respectively, was monitored. The EK- reactor with iron electrodes leads a ~500 mg Pb L -1 reductions and ~1900 mg Pb L -1 recuperations, with electrophoresis phenomenon being predominant. With stainless steel electrodes-based, an homogenization of contaminants was verified, prevalent the electro- osmosis following the flow potential phenomenon. Probably due the material durability, and consequently the high conductivity and possible potential difference. That way, the EK- technique show as an efficient alternative to remediation of contaminated sand by Pb ion.