“Voltametría cíclica y de pulso para detección a nivel milimolecular y trazas de metales pesados en sistemas acuosos y suelos: Cr(VI), Pb (II) y Cu(II))”

Abstract

Resumen del reporte técnico en inglés:

The two most important oxidation states of chromium ion are chromium Cr(III) and chromium Cr(VI) when dissolved in aqueous media. Cation of Cr(VI) is toxic as it had been demonstrated that can induce dermatitis, mutagenesis and has been proved that possess a carcinogenic effect. For this reason, the detection of each one of chromium species is a very important task, although a very challenging task in the same way. In the present work, the implementation of two powerful electrochemical techniques for this detection and quantification was achieved: cyclic voltammetry and differential pulse voltammetry, since they identify redox electrochemical processes of species, and can depict coupled chemical reactions. For the experimentation, a three-electrode array was used, with a gold electrode as working electrode, a platinum wire as a counter electrode and a saturated calomel electrode as a reference electrode. With this arrangement it was possible to measure concentrations of Cr(VI) at 1 mgꞏL-1. With utilization of a standard of Cr(VI) and the use of this arrangement, a calibration curve was performed and the detection at trace level of this toxic toxic metal ion was achieved, with a quantification limit of 0.6118 mgꞏL-1