Electro-hydrometallurgical chloride process for selective gold recovery from refractory telluride gold ores: A mini-pilot study

The current paper introduces for the very first time recently invented electrodeposition-redox replacement (EDRR) method in continuous leaching-recovery-solution purification process. mini-pilot study reveals that longer duration of EDRR process is beneficial as it increases gold recovery per stage and decreases specific energy consumption EDRR. This extraordinary behavior postulated to be inherent process, during cathode surface gradually transformed from stainless steel gold(±copper) surface, thus increasing performance with time. In addition, concentration 1 mg/L PLS was established minimum required efficient operation Gold extraction ore solution throughout pilot test reached up ca. 90%, whereas reference cyanidation only 64% dissolved. Overall, after 150 h experiment, 83% dissolved recovered on cathode, resulting 68.5% holistic ore. Furthermore, simulation model built, suggested closed-loop cupric chloride leaching – copper precipitation can recover total over 84% refractory telluride product, providing further evidence true potential sustainable extraction.