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硫代硫酸盐是一种很有吸引力的替代氰化物用于浸出金矿石的试剂。它的价格比较便宜并且又是无毒的,与金和银能生成比较稳定的络合物,在氨溶液中并在Cu(Ⅱ)的催化作用下很易从金矿石中浸出金。它特别适用于处理那些用氰化法处理时浸出率很低的碳质矿石。然而,过去2 0年间的研究结果表明,在一个完整的工艺过程被证明用于处理典型的金氧化矿石是切实可行和经济合理以前,还有很多问题和障碍都必须了解清楚和设法解决。本文评述了当前对硫代硫酸盐的化学性质和溶解金机理的认识情况,并论述了硫代硫酸盐和连多硫酸盐(M2 SxO6 )的稳定性。接着又对文献中报道的用于浸出各类金矿石的结果进行了评述,还论述了金的回收方案选择和分析了环保与毒性问题。需要作进一步研究的几个问题,包括降低Cu(Ⅱ)或其化氧化剂对硫代硫酸盐的氧化作用、与氰化物相比还需提高金的浸出率、以及了解在不同矿石之间金回收率的变化情况。还需进行一些试验研究工作,以便在用离子交换树脂或其他吸附剂回收金时,尽可能减少连多硫酸盐对金回收率的影响、改进从树脂上洗提铜和金的工艺以及试剂的再循环使用或尽可能降低试剂的浓度
Thiosulfate is an attractive alternative to cyanide used to extract gold ore reagents. It is cheaper and non-toxic, producing stable complexes with gold and silver. It is easy to extract gold from gold ores in ammonia solution and under the catalysis of Cu (II). It is especially suitable for the treatment of carbonaceous ores with very low leaching rates when treated with cyanidation. However, the results of the studies over the past 20 years show that before a complete process proved to be feasible and economically viable for the treatment of typical gold oxide ores, many problems and obstacles must be understood and solved. This paper reviews the current understanding of the chemistry of thiosulfates and the mechanism of dissolved gold and discusses the stability of thiosulfates and polythionates (M2 SxO6). Subsequently, the results reported in the literature for the leaching of various types of gold ore were reviewed, as well as the selection of gold recovery options and the analysis of environmental and toxicological issues. Several issues that require further study include reducing the oxidation of thiosulfate by Cu (II) or its oxidising agents, increasing the leaching rate of gold compared to cyanide, and understanding the gold recovery between different ores The rate of change. Additional experimental work is needed to minimize the effect of polysulfate on gold recovery when recovering gold from ion exchange resins or other adsorbents, to improve the process of eluting copper and gold from the resin, and to Recycle or minimize reagent concentration