ANODIC OXIDATION OF THIOSULFATE IONS IN GOLD LEACHING

来源期刊：中南大学学报(英文版)1997年第2期

论文作者：JIANG Tao Xu Shi Chen Jin Yang Yongbin

文章页码：89 - 91

Key words：thiosulfate; gold leaching; anodic process; electrochemistry

Abstract: The regularities of anodic oxidation of thiosulfate ions on a gold electrode have been investigated using electrochemical methods in order to improve gold extraction. Effects of ammon, copper-ammon ions, pH and sulphite on anodic oxidation of thiosulfate ions have been examined in details. Results show that the anodic oxidation of thiosulfate ions is an inreversible reaction whose oxidizing peak potential is 620 mV/SCE in the absence of ammon. Oxidation rate increases with concentration of thiosulfate ions, but not in linear relation. It is also shown that ammon has significant effects on the oxidation of thiosulfate ions by causing great decrease in oxidation rate and negative shift of peak potential. The degrees of the rate decrease and negative shift increase with ammon concentration. When ammon concentration is increased to 1. 0 mol/L, the oxidation rate decreases to one fourth of that without ammon and the peak potential shifts from 620 mV/SCE to 350 mV/SCE.