cobalt iii sulfide is a mineral of interest for the study of a wide range of bio-chemical processes. It is used as an internal standard in many chromatographic analyses, as well as in the analysis of natural waters and soils.
Typical applications of cobalt are in lithium-ion batteries (electronic devices) and the rechargeable batteries for electric cars. In the year 2018 this industry had quintupled its demand for the element, making it important to find new sources in more stable areas of the world.
In the lab we can make a number of cobalt(III) complexes, all of which are stabilised by a ligand, such as ammonia. The most common are the yellow-orange hexaamminecobalt(III) complexes, which can be produced by air oxidation or hydrogen peroxide in alkaline ammonia solution and in a similar fashion the brown or violet hexaamminecobalt(III) Complexes can be made by e.g. adding sodium chloride to the alkaline ammonia hexaamminecobalt(III) solution.
For more information about these hexaamminecobalt(III) and hexamminecobalt(II) complexes see the IMA guide.
The hexamminecobalt(III) and the hexamminecobalt(II) sulfide can be precipitated by a sufficient amount of a halide salt which is most preferably a chloride salt. Typically from about 10 to about 15 moles of a halide salt are added to the hexamminecobalt(III) ion solution and the resulting mixture is cooled to preferably about 15deg C. The hexamminecobalt(III) is then dissolved in water and separated from the mother liquor by filtration or decantation.
Cobalt is an essential trace element found in the centre of the vitamin B12 molecule, which is needed for the prevention of pernicious anemia and the formation of red blood cells. It is also involved in a wide range of biochemical processes and is required for the production of vitamin K and other erythrocytes.