An Alternative Route to Extract Indium from Chalcopyrite Concentrate

Indium is a significant by-product of zinc metal processing, since it is commonly found with zinc sulfides in the form of solid solution. Recovery of indium in metallurgical processing of zinc is a well-known technique. In addition to the conventional application for zinc concentrates, a wide range of research has been carried out to recover indium from different type of materials such as zinc plant tailings and e-wastes. However, zinc compounds and secondary resources are not the only indium- bearing materials. In this study, an indium carrier chalcopyrite concentrate was subjected to a detailed investigation, and an original process flowsheet was designed. The suggested process included sulfation roasting, cementation, and solvent extraction stages. Impressive results were achieved in terms of overall recoveries and the quality of the end products, with 82.0% In and 98.9% Cu overall recoveries with grades of > 90% for both metals being determined. Also, other products of the process were obtained, as the final leach cake containing 44.49 ppm Au and 3330 ppm Ag.