Gold Recovery from Copper-Gold Tailings by Ammoniacal Thiosulphate Leaching
Article Sidebar
Main Article Content
Abstract
Ammoniacal thiosulphate leaching is a safer method to apply for gold leaching because it does not involve the use of cyanide. It has been found to be a better method than other leaching methods. It is non-toxic and environment-friendly for gold extraction. In this study, the method was developed especially for gold leaching from copper-gold tailings samples. Various factors such as copper(II) sulphate concentration, ammonium thiosulphate concentration, pH, solid-liquid ratio, temperature and rotation speed were studied to determine optimum conditions for leaching. It was found that the most suitable condition were 0.07 M copper(II) sulphate, 0.5 M ammonium thiosulphate, pH = 10, solid-liquid ratio = 1:10, room temperature (30 ºC), rotation speed = 400 rpm and 5 h leaching time. Flame atomic absorption spectrometry was used to analyse the concentration of gold after the leaching process was performed. The performance of ammoniacal thiosulphate leaching method was evaluated by standard material No. ST 279. It was found that the precision of ammoniacal thiosulphate leaching method considered from relative standard deviation value was 2.28%. The accuracy which was considered from the recovery value was 97.63%. The detection limit of gold by flame atomic absorption spectrometry was 0.006 mg/l. The ammoniacal thiosulphate leaching method with optimum condition was applied for gold extraction from copper-gold tailings from northeastern part of Thailand. The results indicated that gold concentration from the ammoniacal thiosulphate leaching method was in the range of 65.52-89.50 g/t. Recovery by the ammoniacal thiosulphate leaching method was greater than 90% as was confirmed by the fire assay standard method.
Keywords: ammoniacal thiosulphate leaching; atomic absorption spectrometry; copper-gold tailings; fire assay; gold
*Corresponding author: Tel.: (+66) 53221385 Fax: (+66) 53225184
E-mail: Kamolwich_in@hotmail.com
Article Details
Copyright Transfer Statement
The copyright of this article is transferred to Current Applied Science and Technology journal with effect if and when the article is accepted for publication. The copyright transfer covers the exclusive right to reproduce and distribute the article, including reprints, translations, photographic reproductions, electronic form (offline, online) or any other reproductions of similar nature.
The author warrants that this contribution is original and that he/she has full power to make this grant. The author signs for and accepts responsibility for releasing this material on behalf of any and all co-authors.
Here is the link for download: Copyright transfer form.pdf
References
Schmidbaur, H., 1999. Gold-Progress in Chemistry, Biochemistry and Technology. Chichester: John Wiley&Sons.
Puddephatt, R.J., 1978. The Chemistry of Gold. Amsterdam: Elsevier.
Rapson, W.S. and Groenewald, T., 1978. Gold Usage. London: Academic Press.
Schmidbaur, H., 1990. The fascinating implications of new results in gold chemistry. Gold Bulletin, 23(1), 11-21.
Schmidbaur, H., Cronje, S., Djordjevic, B. and Schuster, O., 2005. Understanding gold chemistry through relativity. Chemical Physics, 311(1-2), 151-161.
Marsden, J.O. and House, C.I., 2006. The Chemistry of Gold Extraction. 2nd ed. Littleton: Society for Mining, Metallurgy, and Exploration, Inc. (SME).
Petrovic, N., Budelan, D., Cokic, S. and Nesic, B., 2001. The determination of the content of gold and silver in geological samples. Journal of the Serbian Chemical Society, 66(1), 45-52.
Estay, H., Carvajal, P., Gonzalez, K., Yanez, H., Bustos, W., Castro, S. and Arriagada, F., 2013. Cyanide leaching of copper-gold-silver ores. 5th International Seminar on Process Hydrometallurgy, Santiago, Chile, July 10-12, 2013, 153-160.
Oraby, E., Esksteen, J. and Tanda, B., 2017. Gold and copper leaching from gold-copper ores and concentrates using a synergistic lixiviant mixture of glycine and cyanide. Hydrometallurgy, 169, 339-345.
Neelameggham, N.R., Alam, S., Oosterhof, H., Jha, A., Dreisinger, D. and Wang, S., 2015. Rare Metal Technology 2015. Cham.: Springer.
Anderson, C., 2012. Fundamentals of the analysis of gold, silver and platinum group metals. Proceedings of 36th International Precious Metals Institute; a Sure Bet-World Economics Affect Precious Metals, Las Vegas, U.S.A., 2012, 190-216.
Kwaansa-Ansah, E.E., Amenofe, L.P., Armah, E.K. and Opoku, F., 2017. Human health risk assessment of cyanide levels in water and tuber crops from Kenyasi, a mining community in the Brong Ahafo Region of Ghana. International Journal of Food Contamination, 4(16), https://doi.org/10.1186/s40550-017-0061-y
Dube, P.N. and Hosetti, B.B., 2010. Behavior surveillance and oxygen consumption in the freshwater fish Labeo rohita (Hamilton) exposed to sodium cyanide. Biotechnology in Animal Husbandry, 26(1-2), 91-103
Wilson, J., 1983. Cyanide in human disease: A review of clinical and laboratory evidence. Fundamental and Applied Toxicology, 3(5), 397-399.
Medina, D. and Anderson, C.G., 2020. A review of the cyanidation treatment of copper-gold ores and concentrates. Metals, 10(7), 897, https://doi.org/10.3390/met10070897
Societe Generale de Surveillance, 2008. Thiosulphate Leaching - an Alternative to Cyanidation in Gold Processing. [online]. Available at: https://www.sgs.com/-/media/global/documents/flyers-and-leaflets/sgs-min-wa018-thiosulphate-leaching-alternative-to-cyanide-in-gold-processing-en-11.pdf
Aylmore, M.G. and Muri, D.M. 2001. Thiosulphate leaching of gold - a review. Minerals Engineering, 14, 135-174.
Zhang, H.M. and Senanyake, G., 2016. A review of ammoniacal thiosulfate leaching of gold: An update useful for further research in non-cyanide gold lixiviants. Mineral Processing and Extractive Metallurgy Review, 37(6), 385-411.
White, H.A., 1905. The solubility of gold in thiosulfates and thiocyanates. Journal of the Chemical Metallurgical and Mining Society of South Africa, 5, 109-111.
Chen, J., Deng, T., Zhu, G. and Zhao, J., 1996. Leaching and recovery of gold in thiosulfate based system – a research summary at ICM. Transactions of Indian Institute of Metallurgy, 49(6), 841-849.
Ter-Arakelyan, K.A., Bagdasaryan, K.A., Oganyan, A.G., Mkrtchyan, R.T. and Babayan, G.G., 1984. On technological expediency of sodium thiosulphate usage for gold extraction from raw material. lzv. VUZ Tsvetn. Metallurgy, 5, 72-76
Hiskey J.B., 1981. Thiourea as a lixiviant for gold and silver – leaching, recovery and economics. Proceeding of the 100th AIME Meeting, Chicago, USA, 22-26 February 1981, 83-91.
Hancock, R.D., Finkelstein, N.P. and Evers, A., 1974. Linear free energy relationships in aqueous complex formation reactions of the d10 metals ions, Journal of Inorganic Nuclear Chemistry, 36(11), 2539-2543.
Wan, R.Y. and Brierley, J.A., 1997. Thiosulfate leaching following bio-oxidation pretreatment for gold recovery from refractory carbonaceous-sulfidic ore. Mining Engineering, 49(8), 76-80.
Navarro, P., Vargas, C., Villarroel, A. and Alguacil, F.J., 2002. On the use of ammoniacal/ammonium thiosulphate for gold extraction from a concentrate. Hydrometallurgy, 65(1), 37-42.
American Society for Testing and Materials, 2005. Standard Test Method for Fire Assay Determination of Gold in Copper Concentrates by Gravimetry: Annual book of ASTM E 1805-02, West Conshohocken: ASTM International.
Australian Standard, 1991. Methods for the Analysis of Copper, Lead, Zinc, Gold and Silver Ores: Part 1 Determination of Gold (Fire Assay-Flame AAS Method), NSW: Standards Australia.
Arslan, F. and Sayiner, B., 2007. Extraction of gold and silver from Turkish gold ore by ammoniacal thiosulphate leaching. Mineral Processing and Extractive Metallurgy Review, 29(1), 68-82.
Abbruzzese, C., Fornari, P., Massidda, R., Veglio, F. and Ubaldini, S., 1995. Thiosulphate leaching for gold hydrometallurgy. Hydrometallurgy, 39(1-3), 265-276.
Rath, R.K., Hiroyoshi, N., Tsunekawa, M. and Hirajima, T., 2003. Ammoniacal thiosulphate leaching of gold ore. The European Journal of Mineral Processing and Environmental Protection, 3(3), 344-352.
Hung, H.V., Hai, H.T., Nga, N.T, Lee, J.-C. and Jeong, J., 2011. Study on effect of temperature on gold leaching from electronic scraps using thiosulphate with copper(II) catalyst in ammonia media. Journal of Science & Technology, 82A, 37-41.