Leaching of Pyrolusite Ore of Industrial Interest: A Preliminary Study

摘要

The use of the hydrometallurgy for the extraction of manganese from ores not economically treatable by the usual technologies such as pyrometallurgy is actively studied. A Pirolusite (MnO_2) ore of industrial interest has been treated by means of an acid leaching process (by H_2SO_4) using sucrose (C_(12)O-(24)H_(11)) as reducing substance. The process was tested at different temperatures (30deg C 50deg C), acid concentrations (0.01 M - 1 M), reducing substance concentrations (5-20 g/l) and stirring condictions. The influence of the size distribution (<38; 125-180mum) on the leaching yield has been measured. Experimental runs designed by a factorial technique have been carried out. The Analysis of Variance has been used for the evalutation of main effects and cross-interaction of parameters. The possible reactions were proposed and compared with the experimental stoichiomentry. The mesured yields and extraction rates show the potential application of this process to the manganese recovery from ores of industrial interest.