Cyanide-free gold leaching in exceptionally mild chloride solutions

Knowledge Modelling and Comparison of Cyanide-free Gold Leaching Processes - Research Summary

There is increasing pressure from authorities in many countries to find cyanide-free methods for gold processing due to environmental and safety risks. Therefore, it is now under investigation whether the knowledge extraction and formalization procedure can be applied for comparing cyanide-free leaching methods for a certain type of raw material. Research is needed to determine and code the sim...

Intensification Behavior of Mercury Ions on Gold Cyanide Leaching

Cyanidation is the main method used to extract gold from gold raw materials; however, a serious problem with this method is the low leaching rate. In order to improve gold leaching, the intensification behavior of mercury ions on gold cyanide leaching, for two types of materials, sulphide gold concentrate and oxide gold ore, was investigated. The results showed that mercury ions, with only a 10...

COMPARISON OF CYANIDE AND THIOSULPHATE LEACHING FOR GOLD PRODUCTION (A Literature Review)

KINETIC STUDIES FOR GOLD LEACHING OF A REFRACTORY SULFIDE CONCENTRATE BY CHLORIDE–HYPOCHLORITE SOLUTION

In this paper, gold leaching of a refractory sulfide concentrate by chloride–hypochlorite solution was investigated and effects of stirring speed, temperature and particle size on the leaching rate were reported. Experimental data for leaching rate of gold were analyzed with the shrinking–core model. Results were consistent with chemical reaction control mechanism in the first 1 h of leachin...

Leaching of gold ores with high cyanicides: a physico-chemical modeling approach

Processing of gold ores with high sulfide minerals is problematic as they consume cyanide and reduce gold leaching. Optimization of gold leaching and cyanide consumption requires a methodology to estimate the amount of exposed cyanicides, their leaching kinetics, and speciation of cyanide complexes that consume the free cyanide and compete with gold. In this paper, a physico-chemical approach i...