4.3. Electrochemical analysis
The above flotation tests indicated the depressive impact of free cyanide and cuprous cyanide species upon the floatability of minerals, with xanthate as collector. As a significant portion of the precious metals is associated with pyrite, the flotation strategy is aimed at maximising the recovery of pyrite. Electrochemical processes are of particular importance in sulphide systems as a result of their semi-conductive properties. In the following sections, open circuit potential (rest potential), cyclic voltammetry, and impedance spectroscopy were performed to reveal the depressive mechanism of cyanide species via the investigation on their electrochemical responses to pyrite.