Bioleaching of a Copper Sulphide Ore at Different Temperatures

Abstract:

Copper sulphide ore containing 0.37% Cu, with chalcopyrite as the main copper-bearing mineral, was leached in percolation columns containing 20 kg of ore crushed to minus 20 mm at different temperatures 18, 50 and 70°C. The columns were inoculated with cultures of mesophilic, moderately thermophilic and extremely thermophilic chemolithotrophic bacteria, respectively. Different variants of leaching with respect to the composition of the leached solution and the rate of irrigation of the ore were applied at each of the temperatures above-mentioned. The best results were achieved at leaching carried out at 70°C, with periodic additions of ferric ions, nutrients and bacterial cells by leach solutions prepared in a separate BACFOX-type unit, and by application of enhanced aeration of the ore by air enriched in CO₂. 82.1% of the copper was leached in this way within a period of 230 days, while the highest Cu extraction achieved at 18°C was 28.0% and that at 50°C was 55.4%, within the same period of time.

• Periodical: Advanced Materials Research (Volume 825)
• Pages: 258-261
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.825.258
• Online since: October 2013
• Authors: Veneta Ivanova Groudeva, Mihail Vladimirov Iliev, Ralitza Valentinova Ilieva, Stoyan N. Groudev
• Keywords: Bacterial Leaching, Chalcopyrite, Thermophilic Chemolithotrophic Bacteria

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