Catalytic oxidation and kinetics of oxidation of coal-derived pyrite by electrolysis

The catalytic oxidation of coal-derived pyrite (CDP) into SO42- and Fe3+ and kinetics of oxidation of coal-derived pyrite by electrolysis were studied in a batch reactor. In this paper, the influence of electrolysis conditions on the pyrite conversion rate, such as particle size, electrolysis potential, reaction time, etc. was reported. It is obvious that the rate of conversion of pyrite (C-r) increases with the increase of the electrolysis potential, reaction time, temperature, acidity and the concentration of catalyst (MnSO4), but decreases with the increase of concentration of pyrite. The experimental data show that the reaction is marching with shrinking core model. The reaction-controlling step was found to be the reaction between Mn3+ and pyrite. The active energy for oxidation of CDP into SO42- and Fe3+ by electrolysis is 29.6 kJ/mol. (C) 2003 Elsevier Science B.V. All rights reserved.