PRODUCTION OF COBALT AS A CRITICAL METAL FROM PRIMARY AND SECONDARY RESOURCES KRİTİK METAL KONUMUNDAKİ KOBALTIN BİRİNCİL VE İKİNCİL KAYNAKLARDAN ÜRETİMİ

Cobalt is utilised in various high-tech products such as jet engines, super alloys and rechargeable batteries. In view of its relatively high economic importance and supply risk, European Union (EU) has listed cobalt as one of the "critical raw materials". About 84% of cobalt produced from primary resources is extracted as a by-product of copper and nickel production. Production of cobalt, particularly from lateritic nickel ores, is increasing. Recently, hydrometallurgical processes such as high pressure acid leaching (HPAL) are commonly applied for extraction of Ni/Co from laterites. Based on the increasing demand for cobalt, the extraction of cobalt from secondary resources (copper smelting slags, flotation tailings (pyrite concentrates), pyrite ashes) by bio/ hydrometallurgical methods have been extensively investigated. In this paper, the importance of cobalt as a critical raw material, resource potential of cobalt in the world and Turkey, and industrial processes for production of cobalt from ores are reviewed in detail. Previous studies on the recovery of cobalt from primary and secondary resources are discussed. In addition, process flowsheets of various industrial plants for the recovery of cobalt from lateritic ores and flotation tailings in our country are presented.