Leaching Kinetics of Gold Involved in the System S₂O₃^2--EDTA-Cu²⁺

Abstract:

Thiosulphate gold leaching is an alternative technology to the cyanidation of gold ores. Ethylenediaminetetraacetic acid is referred to as EDTA.A study on the leaching kinetics of gold involved in the system S₂O₃^2--EDTA-Cu²⁺ for the gold in this paper. The effect of temperature and of the addition of copper has been also analyzed, temperature has a remarkable effect over the overall reaction rate in the range from 293 to 323k, the result shows that the leaching process conforms to the chemical control model. The concentration of [S₂O₃^2-] considerably affects the leaching rate obtaining a value of for the order of reaction in the range of concentrations from 0.05 to 0.3 mol/L of S₂O₃^2- which obtaining a reaction order of 1.029. Copper addition favored the leaching rate of gold which obtaining a reaction order of 0.441,Thiosulphater addition also favored the leaching rate of gold .kinetics model was established which is 1−(1−x)^1/3=4950.8c (S₂O₃^2-)^1.029c (Cu²⁺)^0.441exp (-9911/8.314T).

• Periodical: Materials Science Forum (Volume 1001)
• Pages: 212-218
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.1001.212
• Online since: July 2020
• Authors: Peng Zhi Xiang*, Chao Deng, Huang Yao, Long Jiang Liu, S. Mogdal
• Keywords: Gold, Kinetics, Leaching, Order of Reaction

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