Changes of Electrode Potential in the No

This study investigates the electrochemical parameters associated with the non-oxidative leaching of Lubin shale middlings using sulfuric acid, focusing on changes in electrode potential and pH. The objective was to determine leaching kinetics and evaluate the mineral/solution interface during the leaching process. Simultaneous measurements of pH and redox potential were conducted with a platinum electrode and copper sulfide mineral electrodes to monitor the leaching dynamics. Results showed a significant decrease in redox potential from +350 mV to +50 mV, indicating that low redox potential prevents the oxidation of copper sulfide minerals and the transition of metals to the solution. The study found that non-oxidative leaching is rapid and selective, effectively decomposing calcium and magnesium carbonates and resulting in carbon dioxide saturation of the leaching slurry. As the degree of carbonate decomposition increased from 50 to 100%, the liberation of metals-bearing minerals significantly improved, facilitating further upgrading and leaching processes. These findings highlight the importance of electrode potential as a critical parameter in optimizing the non-oxidative leaching process.