COBALT: Geology, occurrence, and role in the future green economy

Cobalt is a silvery gray metal that has diverse uses based on certain key properties, including ferromagnetism, hardness, and wear-resistance when alloyed with other metals, low thermal and electrical conductivity, high melting point, multiple valences, and production of intense blue colors when combined with silica. Cobalt is primarily employed in superalloys for turbine engines in jet aircraft and as cathodes in rechargeable batteries. As a result of the accelerated introduction of electric vehicles (EVs), the demand for lithium-ion batteries (LIB) is expected to increase significantly in the future. The top three cobalt-consuming nations in ۲۰۱۱ were China, Japan, and the United States; the annual global consumption of cobalt was roughly ۷۵,۰۰۰ metric tons. In ۲۰۱۱, cobalt, copper, nickel, platinum group element (PGE), and zinc operations generated around ۱۰۹,۰۰۰ metric tons of recoverable cobalt in ores, concentrates, and intermediate products. The main source of mined cobalt in the world was the Democratic Republic of the Congo (Congo [Kinshasa]) (۵۵ percent). The mineralogy of cobalt deposits is diverse and includes both primary (hypogene) and secondary (supergene) phases. Principal terrestrial (land-based) deposit types, which represent most of the world's cobalt mine production, include primary magmatic Ni-Cu(-Co-PGE) sulfides, primary and secondary stratiform sediment-hosted Cu-Co sulfides and oxides, and secondary Ni-Co laterites. The DRC was selected as a case for this study because of its abundant cobalt resources and mining activities. Cobalt is commonly mined as a byproduct of either copper or nickel mining. The DRC leads the world in cobalt production, is the seventh largest mining producer overall (for all metals and minerals), and the ۸th largest producer of copper. The World Bank (۲۰۰۷) estimates that the 'Copperbelt area,' mostly within the former Katanga province of the DRC, contains an estimated ۵۵.۵ million tons of copper and ۳.۶ million tons of cobalt. In ۲۰۱۶, ۱۲۶,۰۰۰ tonnes of cobalt were mined in ۲۰ countries worldwide, with the largest supply coming from the Democratic Republic of the Congo (۵۵% of global cobalt production). Environmental issues related to cobalt mining are mainly concerned with elevated cobalt content in soils and waters. Although at low levels, cobalt is essential to human health (it is the central atom in the critical nutrient vitamin B۱۲), overexposure to high levels of cobalt may cause lung and heart dysfunction, as well as dermatitis. The ecological impacts of cobalt vary widely and can be severe for some species of fish and plants, depending on various environmental factors.

کلیدواژه ها:

Cobalt ، Occurrence ، Green economy ، Electric vehicles