Biological Pretreatment of Refractory Gold Ore by the Fungus, Phanerochaete Chrysosporium

Document Type : Research Article


1 Department of Mining Engineering, Faculty of Engineering, Tarbiat Modares University, P.O. Box 14115-1111 Tehran, I.R. IRAN

2 Department of Chemical Engineering, Tarbiat Modares University, Tehran, Tehran, I.R. IRAN


In this research, fungus Phanerochaete chrysosporium has been used to effectively reduce the gold adsorption ability of carbonaceous matter on one hand, and decompose metal sulfides on the other, to ultimately enhance the gold extraction. Two ranks of coal (ordinary and anthracite) were used as substitutes to investigate the ability of fungus to reduce the gold adsorption by carbonaceous matter. The results showed that the ability of anthracite coal in gold adsorbing is 5 times more than ability of ordinary one. Phanerochaete chrysosporium reduced the ability of anthracite by over 85% for a 21 days culturing period under processing in PBD (Potato Dextrose Broth) medium and 95% for the same period in MWB (Millet and Wheat Bran) medium. Phanerochaete chrysosporium has also ability to oxidize the sulfide existing in refractory gold ores. The pyrite initial weight decreased by 35% for pH equal 7 and 30% for pH equal 4 in 21 days of processing. Pretreatment was performed for Zarshouran refractory gold ore with different percentage of orpiment and gold. After a 14 days of processing, the amount of gold extraction by cyanidation of samples (1) (-2210 µm fraction containing less orpiment than natural samples),(2) (similar to natural samples from the amount of orpiment point of view), and (3) (+2210 µm  fraction containing enriched over 85% orpiment) increased to 30%, 25% and 1% respectively and sulfide mineral existing in samples (1) and (2) both decreased by over 50%. According to the results, Phanerochaete chrysosporium is a microorganism with high potential for oxidizing the sulfide minerals and neutralizing the carbonaceous matter existing in refractory gold ore simultaneously and totally, it has a high potential for increasing the gold recovery in cyanidation of refractory gold ore.


Main Subjects

[1] Marsden J.O., House C.I., The Chemistry of Gold Extraction, 2nd ed. Society for Mining, Metall. Explor. (SME), Littleton, Co, USA, (2006).
[3] Arriagada F. J., Osseo-Asare K., Gold Extraction from Refractory Ores: Roasting Behavior of Pyrite and Arsenopyrite. In: Kudryk, V., Corrigan, D. and Liang, W. W. (Eds.), "Precious Met. Mining, Extr. Process.", The Metallurgical Society of AIME, Warrendale, PA: 367-385 (1984).
[4] Osseo-Asare K., Afenya P.M., Abotsi G.M.K., Carbonaceous Matter in Gold Ores: Isolation, Characterization and Adsorption Behavior in Aurocyanide Solutions. In: Kudryk V., Corrigan D., Liang, W. W. (Eds.), Precious Met. Mining, Extr. Process., Los Angeles: 125-144 (1984).
[5] Hausen D.M., Bucknam C.H., Study of Preg Robbing in the Cyanidation of Carbonaceous Gold Ores from Carlin, Nevada. In: Park, W. C., Hausen, D. M. and Hagni, R. D. (Eds.), "Appl. Mineral.", Proceedings of the Second International Congress on Applied Mineralogy, AIME, Warrendale, PA: 833-856 (1984). 
[6] M., Treatment of Carbonaceous Refractory Gold Ores, Miner. Eng., 4(7): 1043-1055 (1991).
[7] Ibrado A.S., Fuerstenau D.W., Effect of the Structure of Carbon Adsorbents on the Adsorption of Gold Cyanide, Hydrometallurgy, 30(1): 243-256(1992).
[8] Amankwah R.K., Yen W.T., Ramsay J.A., A Two-Stage Bacterial Pretreatment Process for Double Refractory Gold Ores, Miner. Eng., 18(1): 103-108(2005).
[10] Brierley C.L., Bacterial Oxidation, Eng. Min. journal. New York NY, 196(5): 42-44(1995).
[11] Martinko J.M., Madigan M.T., "Brock Biology of Microorganisms, Englewood Cliffs", NJ: Prentice Hall. ISBN 0-13-144329-1,(2005).
[12] Amankwah R.K., Yen W.T., Effect of Carbonaceous Characteristics on Biodegradation and Preg-Robbing Behavior, in: "Proceedings of 23rd Annual Meeting of International Mineral Processing Conference",Istanbul, Turkey, 2: 1298-1302(2006).
[15] Ofori-Sarpong G., Osseo-Asare K., Tien M., Fungal Pretreatment of Sulfides in Refractory Gold Ores, Miner. Eng., 24(6): 499-504 (2011).
[16] Kersten P.J., Kirk T.K., Involvement of a New Enzyme, Glyoxal Oxidase, in Extracellular H2O2 Production by Phanerochaete chrysosporium, J. Bacteriol., 169(5): 2195-2201 (1987).
[17] Ofori-Sarpong G., Osseo-Asare K., Tien M., Mycohydrometallurgy: Biotransformation of Double Refractory Gold Ores by the Fungus, Phanerochaete chrysosporium,, Hydrometallurgy, 137: 38-44 (2013).