The Influence of Pyrite on Galvanic Assisted Leaching of Chalcocite Concentrates

Abstract:

The dissolution of metal sulfides is controlled by their solubility product and valence bond theory, pyrite and chalcocite have different electronic nature of the valence energy band, with which the electrolyte may exchange electrons during dissolution reaction, so they have different principals of dissolution. Pyrite which has a higher rest potential is galvanically protected, while chalcopyrite which has a lower rest potential is preferentially leached. Pyrite is intentionally added to the leaching of chalcocite concentrates, we investigated the influence of pyrite to chalcocite weight ratio, solution pH , Eh and the presence of bacteria on assisted leaching of chalcocite concentrates. The leaching solution redox potential, pH, iron, copper and bacteria were monitored, leached residue was collected and analysed to understand leaching mechanism. We found that chalcocite leaching efficiency is enhanced with pyrite:chalcocite weight ratio increased.

• Periodical: Advanced Materials Research (Volume 825)
• Pages: 459-463
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.825.459
• Online since: October 2013
• Authors: Biao Wu, X.L. Yang, L.L. Cai, G.C. Yao, J.K. Wen, D.Z. Wang
• Keywords: Chalcocite, Galvanic Leaching, Pyrite

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