The Dissolution Behavior of Metals from Ag/Cu and Ag/Cu Alloys in Acidic and Cyanide Solutions

다국어 초록 (Multilingual Abstract)

The dissolution behavior of silver, copper, and gold from silver/copper and silver/gold alloys in acid and cyanide solutions has been investigated using a rotating disc. Oxygen or ferric ion was used as an oxidant. The effect of composition of alloys, rotation speed, concentration of lixiviants, and temperature on the overall dissolution kinetics of these metals has been studied.
The dissolution rate of silver was reduced due to galvanic effect, when it was leached from a silver/copper alloy disc in acidic media at relatively low oxidation potentials. On the other hand, when the oxidation potential was high, the galvanic effect of the dissolution rate became less pronounced. In the case of the silver/gold system in cyanide solutions, the effect of alloy composition on the dissolution rate of gold and silver was not as much as in the case of silver/copper alloy systems. This may be attributed to the fact that both gold and silver are noble, and therefore, the electromotive forces of these two metals are not significantly different.