Abstract
In order to obtain a fundamental information on the selective separation of Au from a non-oxidative acidic chloride solutions containing chloride complex ions of precious metals such as Au, Pt and Pd, the selective precipitation of Au by using a reduction method with CuCl2− ions was investigated from the electrochemical and kinetic points of view.
In the present study the electrochemical method was used to determine the anodic and cathodic polarization curves of Pt and Au electrodes in an acidic chloride solution containing AuCl4− and CuCl2− ions, the stoichiometry of reductive precipitation of Au with CuCl2− ions and the selective separation of Au from the solution containing chloride complex ions of precious metals such as Au, Pt and Pd.
From the experimental results, it has been concluded that Au can be selectively precipitated with CuCl2− ions from the non-oxidative acidic chloride solution containing chloride complex ions of Au and Pd.
However, the selective separation of Au from the solution containing complex ions of Au and Pt is difficult. On the other hand, the electrochemical measurement of the anodic and cathodic polarization curves of Pt and Au electrodes is useful in predicting the reductive precipitation behavior of Au with CuCl2− from the solution containing chloride complex ions of precious metals.
