Cyclic voltammetry applied to the characterisation of galena

We propose a simple and rapid method to characterise galena and evaluate sample purity directly from powdered ore without previous treatment, using cyclic voltammetry. Lead sulphide samples from galena concentrates produced by flotation, natural galena and an analytical reagent (AR) lead sulphide salt were tested using carbon paste electrodes (CPE) in a chloride electrolyte medium of pH = 2. The voltammograms demonstrate that among the three types of samples tested, oxidation potentials for galena do not vary. However, the natural galena sample differed in the magnitude of oxidation currents and in the shape of the oxidation peak from the concentrate and salt samples. This method took advantage of current and peak variation to permit the rapid and qualitative identification of the nature of a galena sample, and at the same time, it was used for the quantitative determination of galena present in the flotation concentrate samples. (C) 1999 Elsevier Science B.V. All rights reserved.