Electrochemical study of binary and ternary copper complexes in ammonia-chloride medium

Electrochemical and spectroscopic analyses (UV–vis and XRD) have been applied to evaluate the speciation of copper in ammonia-chloride solutions. The conditions for these analyses were established through thermodynamic studies that included predominance existence and Eh–pH diagrams. These studies highlighted the importance of copper ternary complexes and showed how the solubility of Cu(I) and Cu(II) increases over a wide range of pH when copper ternary complexes are formed. Hence, it has been elucidated the copper, ammonia and chloride concentrations that makes existence of these so-called copper ternary complexes, possible.