Modeling the Process of Au Sorption by Natural Sorbents in the Conditions of the Dispersion Train of a Sulfide Tailings

The experimental study is aimed at elucidation the laws of Au sorption/deposition by various natural sorbents in an acidic environment (pH=2). The experiments simulated the conditions of the dispersion train of the Ursk tailings (Kemerovo region, Russia), where active concentration of Au by natural organic matter in an acidic environment is observed. It was found that the degree of extraction of gold from a sulfate solution is generally higher than from chloride solution. This may indicate higher thermodynamic stability of Au chloride complexes in an acidic environment than sulfate ones. Higher deposition rates of gold are observed in solutions with a predominant content of sulfate ions. According to the degree of deposition of Au, a series was established (from larger to smaller): a mixture of clay minerals (smectite + palygorskite + muscovite) > humic acids > kaolinite