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Acid leaching and dissolution of major sulphide ore minerals: processes and galvanic effects in complex systems

  • P. K. Abraitis (a1), R. A. D. Pattrick (a1), G. H. Kelsall (a2) and D. J. Vaughan (a1)

Abstract

The kinetics and mechanisms of dissolution of the major base metal sulphide minerals, pyrite, chalcopyrite, galena and sphalerite in acidic (chloride) media have been investigated. Minerals were ground in air, then dissolved in air-equilibrated solutions at pH 2.5, while monitoring the redox potential. Solution samples were analysed by ICP-AES and HPLC, and surfaces of residual sulphides analysed using XPS. Dissolution of aerial oxidation products on pyrite particles in the first 15 min apparently led to a sulphur-rich surface, and was followed by slower dissolution of pyrite itself, driven by oxygen reduction, and resulting in net production of protons. Chalcopyrite dissolution resulted in a Cu, S-rich (near) surface layer, accompanied by net consumption of protons. Apparently incongruent dissolution of galena and sphalerite may reflect the formation of elemental S at the surface. The rates of dissolution of chalcopyrite, galena and sphalerite in the presence of pyrite were determined, respectively, as 18, 31 and 1.5 times more rapid than in single-mineral experiments. These data were consistent with galvanically-promoted mineral oxidation of the other sulphides in the presence of pyrite. In the case of galena, the experimental data suggested extensive release of Pb ions and development of a sulphur-rich surface during galvanically-promoted dissolution.

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Present address: BNFL plc, BTC (B170), Sellafield, Seascale, Cumbria, UK

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Biegler, T., Rand, D.A.J. and Woods, R. (1970) Oxygen reduction on sulphide minerals. Part 1. Kinetics and me cha ni sm a t rot at ed pyr it e e le ct rod es. Electro analyt ical Chemistry and Interfacial Electrochemistry, 60, 151162.
Bonnissel-Gissinger, P., Alnot, M., Erhardt, J. and Behra, P. (1998) Surface oxidation of pyrite as a function of pH. Environmental Science and Technology, 32, 28392845.
Craig, J.R. and Vaughan, D.J. (1994) Ore Microscopy and Ore Petrography (2nd edition). Wiley Interscience, New York.
Karthe, S., Szargan, R. and Suoninen, E. (1993) Oxidation of pyrite surfaces: a photoelectron spectroscopic study. Applied Surface Science, 72, 157170.
Keith, C.N. and Vaughan, D.J. (2000) Mechanisms and rates of sulphide oxidation in relation to the problems of acid rock (mine) drainage. Pp. 197219 in: Environmental Mineralogy: Microbial Interactions, Anthropogenic Influences, Contaminated Land and Waste Management (Cotter-Howells, J.D., Campbell, L.S., Valsami-Jones, E. and Batchelder, M., editors). Mineralogical Society Series 9, Mineralogical Society, London.
Nesbitt, H.W. and Muir, I.J. (1994) X-ray photoelectron spectroscopic study of a pristine pyrite surface reacted with water vapour and air. Geochimica et Cosmochimica Acta, 59, 46674679.
Smith, E.E. and Schumate, K.S. (1970) Sulfide to Sulfate Reaction Mechanism. Federal Water Quality Administration Water Polution Control Research Series Report # 14010, FPS, 02/70.
Subrahmanyam, T.V. and Forssberg, K.S.E. (1993) Mineral–solution interface chemistry in minerals engineering. Minerals Engineering, 6, 439–454 Vaughan, D.J., England, K.E.R., Kelsall, G.H. and Yin, Q. (1995) Electrochemical oxidation of chalcopyrite (CuFeS2) and the related metal-enriched derivatives Cu4Fe5S8, Cu9Fe9S16 and Cu9Fe8S16. American Mineralogist, 80, 725731.
Williamson, M.A. and Rimstidt, J.D. (1994) The kinetics and electrochemical rate-determining step of aqucous pyrite oxidation. Geochimica et Cosmochimica Acta, 58, 54435454.
Yin, Q., Kelsall, G.H., Vaughan, D.J. and England, K.E.R. (1995) Atmospheric and electrochemical oxidation of the surface of chalcopyrite (CuFeS2). Geochimica et Cosmochimica Acta, 59, 10911100.

Keywords

Acid leaching and dissolution of major sulphide ore minerals: processes and galvanic effects in complex systems

  • P. K. Abraitis (a1), R. A. D. Pattrick (a1), G. H. Kelsall (a2) and D. J. Vaughan (a1)

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