Degradation of Thiosulfate in the Process of Gold Leaching

摘要

Thiosulfate is a promising alternative for the hydrometallurgical treatment of gold ores. Degradation of thiosulfate before leaching and in the process of gold as well as the behaviours of tetrathionate and trithionate by electrochemical methods is investigated in this work. Results are reported for the analysis of gold thiosulfate leach solutions and it is shown that tetrathionate and pentathionate are the dominant reaction products from thiosulfate oxidation. Trithionate was the main reaction product within certain range of hydroxide concentrations (0.0001-0.01 M), tetrathionate concentration decreases as the hydroxide concentration increases when pH is greater than 13 which show tetrathionate can be readily decomposed to thiosulfate and trithionate by raising the pH. Degradation of thiosulfate in the process of gold leaching was carried out in the paper by electrochemical methods, The result shows that 43.57 % of thiosulfate in solution had consumed after 24 h.