Cobalt

Kobalt 13g

Cobalt(II)-chloride-hexahydrate-sample

Tetrakis(1-norbornyl)cobalt(IV)

Early blue and white ware circa 1335 Jingdezhen

Cobalt OreUSGOV

Cobalt is a chemical element with the symbol Co and atomic number 27. It is found naturally only in chemically combined form, with the most common forms being in minerals. Cobalt is a hard, lustrous, silver-gray metal that is a byproduct of the mining of nickel and copper. Due to its magnetic properties, cobalt is used in the production of alloys that retain their strength at high temperatures and are used in the manufacture of jet engines, gas turbines, and magnetic materials. Cobalt is also an important component of rechargeable batteries, including lithium-ion batteries, which are widely used in electric vehicles and portable electronics.

Properties and Occurrence

Cobalt has a relative density of 8.9 and a melting point of 1495°C. It is ferromagnetic up to 1121°C, which is the highest temperature of any material. Cobalt's properties, such as wear resistance, high temperature strength, and resistance to corrosion, make it valuable in a variety of applications.

The element is most frequently obtained as a byproduct of mining and refining nickel and copper. Major cobalt production occurs in the Democratic Republic of the Congo, which is the largest producer, followed by Russia, Australia, and Canada.

Uses

Cobalt's uses can be categorized into several areas:

Alloys

Cobalt-based superalloys are used in the aerospace industry for parts of jet engines that are subjected to high temperatures and stress. It is also used in the production of steel for its properties of adding strength and resistance to wear and corrosion.

Batteries

Cobalt is a critical material in the production of rechargeable batteries, including lithium-ion, nickel-cadmium, and nickel-metal hydride batteries. These batteries are used in a wide range of applications from electric vehicles to portable electronic devices.

Catalysts

Cobalt is used as a catalyst in the petroleum and chemical industries, particularly in processes such as Fischer-Tropsch synthesis for converting natural gas into liquid fuels.

Colorants

Cobalt salts are used to produce a distinctive deep blue color in glass, ceramics, inks, paints, and varnishes. Cobalt blue is a notable pigment that has been used in art and decoration for centuries.

Health and Safety

Cobalt is an essential element for human health in very small amounts as part of Vitamin B12. However, exposure to cobalt dust or compounds can be harmful, causing skin and lung issues, and prolonged exposure can lead to more serious health problems. Safety guidelines and exposure limits have been established to protect workers in industries where cobalt is processed or used.

Environmental Impact

The mining and refining of cobalt can have significant environmental impacts, including habitat destruction, water pollution, and air pollution. Efforts are being made to reduce the environmental footprint of cobalt mining and to recycle cobalt from used batteries and other sources.