Effects of Quebracho Tannin on Recovery of Colloidal Gold from Bioleached Wash Liquor
Keywords:
Quebracho Tannin, pyrite, arsenopyrite, gold processing, colloidal particles, flotation concentrateAbstract
Gold occurs in some concessions as submicron particles in pyrite and arsenopyrite, which is processed in a flotation concentration to obtain gold enriched sulphide concentrate. The concentrate is then treated in a biological oxidation step to oxidize the sulphides and liberate the occluded gold and make them amenable for cyanidation. The oxidized sulphide concentrate with high acidic content is washed in Counter-Current Decantation (CCD) thickeners to obtain thickened slurry, from which gold is recovered by cyanidation and wash liquor which is considered as tailings. The wash liquor from the CCD thickeners of a typical BIOX plant in Ghana, Golden Star Resources Limited carries away 0.57 g/L of gold to tailings. This paper considered effects of Quebracho Tannin (QT) on recovery of gold from the oxidized flotation concentrate wash liquor. The effect of Quebracho Tannin on Total Suspended Solids (TSS) was also established. This research established that the gold lost to tailings was not soluble in the effluent but was mainly in the form of colloidal particles. Application of Quebracho Tannin to CCD effluent showed a substantial decrease in the loss of gold to tailings. About 0.13 g of gold was recovered from the CCD effluent per tonne of ore treated. An optimum QT dose of 0.05 g/l was determined from laboratory test giving a 21.25 % reduction in the Total Suspended Solids (TSS) and a 45.79 % reduction in the gold loss to tailings. When the 0.05 g/l dose was applied on the plant the TSS reduced by 53.51 %.
References
Ahmed-Salim, A., (2009), “Bogoso BIOX® Plant: An update on performance, challenges and opportunitiesâ€, Golden Star (Bogoso/Prestea) Ltd, 14 pp.
Atanassova, M. and Christova-Bagdassarian, V., (2009), “Determination of Tannins Content by Titrimetric Method for Comparison of Different Plant Speciesâ€, Journal of the University of Chemical Technology and Metallurgy, pp 413 – 415.
Cosgrove, T., (2005), Colloid Science: Principles, Methods and Applications, Blackwell Publishing Ltd, United Kingdom, 288 pp.
Fridrikhsberg, D. A., (1986), A Course in Colloid Chemistry, Mir Publishers, Moscow, 424 pp.
Gaudin, A. M., (1939), Principles of Mineral Dressing, McGraw-Hill Book Company, Inc., New York and London, 554 pp.
MaleÅ¡ev, D. and Kuntić, V., (2007), “Investigation of metal-flavonoid chelates and the determination of flavonoids via metal-flavonoid complexing reactionsâ€, Journal of Serbia Chemical Society, 72 (10) pp 921-939.
Marsden, J. O. and House, C. I., (2006), The Chemistry of Gold Extraction, Society of Mining, Metallurgy, and Exploration, Inc. Publishers, Littleton, Colorado, USA 80127, 651 pp.
McRae, J. M. and Kennedy, J. A., (2011), “Wine and Grape Tannin Interactions with Salivary Proteins and Their Impact on Astringency: A Review of Current Researchâ€, Molecules Journal 16, pp 2348 – 2364.
Okuda, T. and Ito, H., (2011), “Tannins of Constant Structure in Medicinal and Food Plants – Hydrolysable Tannins and Polyphenols Related to Tanninsâ€, Molecules Journal 16, pp 2191 – 2217.
Shaw, J. D., (1992), Introduction to Colloid and Surface Chemistry, Butterworth Heinemann Publishers, Burlington, 306 pp.
Traw, M. B. and Nancy, G., (2010), “Environmental Microbiology: Tannins & Microbial Decomposition of Leaves on the Forest Floorâ€, The American Biology Teacher, Vol. 72, No. 8, pp 506 – 512.
Wills, B. A. and Napier-Munn, T. J., (2006), Mineral Processing Technology, 7th edition, Elsevier Science and Technology Books Publishers, 444 pp.
Downloads
Published
Issue
Section
License
Copyright © 2021 University of Mines and Technology (UMaT), Tarkwa. Ghana
