硫代硫酸盐浸金电化学研究 (Ⅰ)金的阳极溶解行为及机理

来源期刊：中南大学学报(自然科学版)1993年第2期

论文作者：陈荩 姜涛 许时

文章页码：169 - 173

关键词：硫代硫酸盐; 浸出; 金; 电化学; 阳极过程

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

摘    要：采用各种电化学方法对金在硫代硫酸盐溶液中阳极溶解的行为及机理进行的研究表明,无氨时,金的阳极溶解约在50mV(SCE)出现电流峰,极化曲线有明显的钝化特征,金的阳极溶解速度较慢;氨对金的阳极溶解有显著的促进作用,它使钝化作用减弱,金的溶解速度增大。金在含氨的硫代硫酸盐溶液中的溶解机理是:氨优先与金粒表面阳极上的金离子络合,生成的金氨络离子进入溶液后被硫代硫酸根离子取代,生成最终产物金硫代硫酸根离子。

Abstract: In this paper,the behaviour of anodic dissolution of gold in thiosulfate solution has beeninvestigated.Results show that the current peak of anodic dissolution of gold occurs at about50 mV(SCE).The dissolution rate is very low and there is passivation in the polarizationcurves in the absence of ammonia.Ammonia presents a very positive effect on the anodic dis-solution.Mechanism of anodic dissolution of gold in ammoniacal thiosulfate solution is pro-posed based on the results.Ammonia reacts with gold ions on anodic of gold,forming goldammonia complex ions,which are substituted by thiosulfate ions after entering the solutionto result in stabler gold thiosulfate complex ions.