Effect of Carbon-bearing Minerals on cyanide leaching
2020-08-10 09:32Introduction：Effect of Carbon-bearing Minerals on cyanide leaching The results show that the dissolved gold in the leaching solution of sodium cyanide will be adsorbed on the surface of the mineral when the content of carbon with high adsorption activi
Effect of Carbon-bearing Minerals on cyanide leaching
The results show that the dissolved gold in the leaching solution of sodium cyanide will be adsorbed on the surface of the mineral when the content of carbon with high adsorption activity in gold ore is high, which results in the loss of gold in the cyanide tailings.In order to eliminate the harmful effect of carbonaceous substances on the cyanide extraction of gold, the method of decarbonization before cyanidation or masking with chemicals can be used. Methods of pre-decarbonization before cyanidation include:
1. Before cyanidation, decarbonization is carried out by physical methods (such as flotation method). When the removed carbonaceous substance contains gold, it can be treated separately after oxidizing and roasting.
2. Removal of carbon by oxidative roasting before cyanidation (suitable for high grade carbon-bearing ores or carbon-bearing gold concentrate)
3. The ore pulp before cyanidation was oxidized with sodium hypochlorite as a strong oxidant. The basic condition was that sodium hypochlorite of 9kg/t was added in alkaline medium at 50 ~ 60 ℃ and stirred for 3 ~ 4 hours.
A few kerosene and coal tar can be added for other cyanidation processes outside CIL to form a film on the surface of carbon to hinder the adsorption of dissolved gold and silver. However, the carbon slurry method can not do this, because this kind of chemicals will seriously pollute the activated carbon and reduce the adsorption index in the carbon adsorption process after leaching.
