A study of the electroleaching of manganese ore

Electrochemical processing has been adopted to upgrade the Egyptian low-grade manganese ores. In order to establish the contribution of the different mineral species to the electrochemical behavior of the ore in sulphuric acid solutions, cyclic voltammetric studies were carried out. The effects of acid concentrations (25-100 g l(-1)), Mn2+, Fe2+ ion concentrations and temperature on the voltammograms were followed. Electroleaching experiments using a platinum gauze feeder electrode as a slurry electrode were carried out. The experimental conditions that were required to enhance the selective extraction of manganese from its low-grade ore were in agreement with those observed for the raw material incorporated in carbon paste electrodes. Maximum leaching rate was achieved at 0 mV vs. a Hg/Hg2SO4/K2SO4 reference electrode. The morphology and structure of the undissolved matter were examined by optical and electron microscopy. (C) 2000 Elsevier Science B.V. All rights reserved.