Corrosion and Electrochemical Oxidation of a Pyrite by Thiobacillus ferrooxidans.
The oxidation of a pure pyrite by Thiobacillus ferrooxidans is not really a constant phenomenon; it must be considered to be more like a succession of different steps which need characterization. Electrochemical studies using a combination of a platinum electrode and a specific pyrite electrode (packed-ground-pyrite electrode) revealed four steps in the bioleaching process. Each step can be identified by the electrochemical behavior (redox potentials) of pyrite, which in turn can be related to chemical (leachate content), bacterial (growth), and physical (corrosion patterns) parameters of the leaching process. A comparison of the oxidation rates of iron and sulfur indicated the nonstoichiometric bacterial oxidation of a pure pyrite in which superficial phenomena, aqueous oxidation, and deep crystal dissolution are successively involved.
Mustin
C
C
Centre de Pédologie Biologique du C.N.R.S., UPR 6831 Associée à l'Université de Nancy I, 17 Rue Notre-Dame-des-Pauvres, B. P. 5, and Ecole Nationale Supérieure de Géologie, Laboratoire "Environnement et Minéralurgie," U. R. A. 235 du C.N.R.S., B. P. 40, 54501 Vandoiuvre-les-Nancy Cedex, France.
Berthelin
J
J
Marion
P
P
de Donato
P
P