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Chromite is a crystalline mineral composed primarily of iron(II) oxide and chromium(III) oxide compounds. It can be represented by the chemical formula of FeCr 2 O 4 . It is an oxide mineral belonging to the spinel group .
The mineral chromite is an iron chromium oxide with empirical formula FeCr 2 O 4. Structurally, it belongs to the spinel group. Magnesium can substitute for iron in variable amounts as it forms a solid solution with magnesiochromite (MgCr 2 O 4);. [1] Zincochromite is another example.
Pure chromium metal is produced by a different process: roasting and leaching of chromite to separate it from iron, followed by reduction with carbon and then aluminium. Trivalent chromium (Cr(III)) occurs naturally in many foods and is sold as a dietary supplement , although there is insufficient evidence that dietary chromium provides ...
It is derived from the mineral chromite, (Fe,Mg)Cr 2 O 4. The conversion of chromite to chromia proceeds via Na 2 Cr 2 O 7, which is reduced with sulfur at high temperatures: [7] Na 2 Cr 2 O 7 + S → Na 2 SO 4 + Cr 2 O 3. The oxide is also formed by the decomposition of chromium salts such as chromium nitrate, or by the exothermic ...
It is usually found as the mineral chromite, from which ferrochrome is produced in a smelting process. Rank Country/Region Chromium ore production (tonnes)
One of the world's poorest nations sits on abundant deposits of iron, lead, lithium and other minerals, possibly worth trillions of dollars.
The primary chromium ore is the mixed metal oxide chromite, FeCr 2 O 4, found as brittle metallic black crystals or granules. Chromite ore is heated with a mixture of calcium carbonate and sodium carbonate in the presence of air. The chromium is oxidized to the hexavalent form, while the iron forms iron(III) oxide, Fe 2 O 3:
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