Article ID Journal Published Year Pages File Type
213076 Hydrometallurgy 2009 7 Pages PDF
Abstract

The solubility of malachite in the presence of ammonia, ammonium chloride and their mixed solution is calculated by a geochemical modeling code and is measured in a series of dissolution experiments using synthetic malachite at 25 °C. The simulated results show a good agreement with the experimental data gained at 25 °C. The predicted and experimental results indicate that the precipitate CuO limits the copper solubility in aqueous ammonia and Cu(OH)1.5Cl0.5 in aqueous ammonium chloride. For a mixed solution containing ammonia and ammonium chloride, highest copper solubility can be achieved by adjusting the [NH3]/[NH4Cl] ratio to about 2:1. The thermodynamic model presented rationalises the interactions between the different components and predicts the influence of changes in the concentration of ammonia and ammonium chloride on the copper solubility of malachite.

Related Topics
Physical Sciences and Engineering Chemical Engineering Chemical Engineering (General)
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