DESCRIPTION
Chromium is a chemical element with atomic number Z=24 and is found in group 6 of the periodic table of the elements. Its name “chromium” (derived from the Greek chroma, “color”) is due to the different colors of its compounds.
The usual method of obtaining chromium is as follows: first, the ore is heated together with the addition of calcium carbonate and sodium carbonate in the presence of air. The chromium is oxidized to its hexavalent form.
Subsequently, the chromate is transformed into oxide by reaction with sulfuric acid. Once the oxide is obtained, it is reduced to chromium metal by an aluminothermic process.
Elemental chromium is not found in nature. Its most important mineral due to its abundance is chromite.
PROPERTIES
Chromium is silvery white, hard and brittle. However, it is relatively soft and ductile when very pure. Its main uses are in the manufacture of corrosion-resistant alloys, such as stainless steel, which are very hard and heat-resistant, and as a coating for galvanizing.
Chromium metal is not classified as a hazardous substance by the EU and is not considered dangerous goods for transport.
APPLICATIONS
- Manufacture of stainless steels and other anti-corrosion alloys.
- Chrome plating coatings.
- Colorants.
- Catalysts.
