Abstract
AbstractThe electrochemical behavior of gold dissolution in the Cu2+–NH3–S2O32−–EDTA solution has been investigated in detail by deriving and analyzing the Tafel polarization curve, as this method is currently widely implemented for the electrode corrosion analysis. The dissolution rate of gold in Cu2+–NH3–S2O32−–EDTA solution was determined based on the Tafel polarization curves, and the effects of various compound compositions in a Cu2+–NH3–S2O32−–EDTA mixture on the corrosion potential and corrosion current density were analyzed. The results showed that the corrosion potential and polarization resistance decreased, whereas the corrosion current density increased for certain concentrations of S2O32−–NH3–Cu2+and EDTA, indicating that the dissolution rate of gold had changed. The reason for promoting the dissolution of gold is also discussed.
Highlights
Gold extraction has always been a highly polluting and toxic process due to the use of cyanide [1]
The electron transfer rate is proportional to the rate of gold dissolution due to the electron transfer in the process of gold dissolution; the dissolution rate of gold can be described by the corrosion current density (Jcorr)
When the concentration of S2O32− was increased from 0.01 to 0.1 mol/L, the corrosion current density increased from 0.540 × 10−6 to 1.714 × 10−6 A/cm2
Summary
Gold extraction has always been a highly polluting and toxic process due to the use of cyanide [1]. It has been reported that the anodic dissolution of gold can be controlled by an electrochemical reaction under certain conditions [31,32]. The effects of composition on gold dissolution in thiosulfate solution 497 gold dissolution in the Cu2+–NH3–S2O32−–EDTA solution by employing the standard electrochemical method and by subsequently deriving and analyzing the steadystate polarization curves and the constant-current step curves [21,22,23]. The Tafel polarization curve is an important tool for the analysis of electrode corrosion, there are few reports on the dissolution mechanism of gold in Cu2+–NH3–S2O32−–EDTA solutions. The dissolution rate of gold in a Cu2+–NH3–S2O32−–EDTA mixture was determined by deriving and analyzing the Tafel polarization curves, and the effects of modifying the composition of a Cu2+–NH3–S2O32−–EDTA mixture on the dissolution behavior of gold were analyzed. The mechanisms for promoting gold dissolution and the main control steps of the gold leaching reaction are discussed
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
