LEACHING OF CU2O WITH AQUEOUS-SOLUTION OF SULFUR-DIOXIDE

Leaching of Cu2O with aqueous SO2 solution is significant, since durin g the dissolution process, precipitation of copper as Chevreul's salt also takes place under appropriate conditions. The dissolution is cont rolled by surface reactions and proceeds through both aqueous SO2 and acid dissolution paths. An overall rate equation based on the above pr emise has been found to agree well with the experimental data. At pH v alues higher than 1.8, precipitation of copper as Chevreul's salt take s place after about 10 minutes of leaching. The extent of the precipit ation depends upon the pH, SO2 concentration, initial Cu2+ concentrati on, and sulfate concentration in the leaching solution.