Feasibility of electrokinetic in situ leaching of gold

This study was designed to verify the in-principle feasibility of this novel technique. A series of laboratory experiments was performed with an iodide/tri-iodide solution as lixiviant to extract gold from unconsolidated porous media. Experiments in which pyrite was included as proxy gangue mineral and complimentary bottle roll tests showed a declining efficiency of EK-ISL gold leaching with increasing pyrite oxidation. However, 80% gold recovery was still achieved, even with the highest tested pyrite concentration (5.26 wt%). The coupled transport and reaction processes were interpreted and quantified through numerical model simulations that were constrained by the experimental observations. Overall the experimental and numerical modeling results suggest the in-principle feasibility of EK-ISL.