Extraction of Iron

Extraction of Iron
Iron:
Atomic Number: 26
Electronic configuration: [Kr]3 d⁶4s²)

Iron is extracted from its oxide ore especially from the magnetite, haematite and limonite ores. The extraction involves the following steps:

1. Concentration of ore: The ore is concentrated by gravity separation. The washed ore is then subjected to electromagnetic separation.
    
2. Calcination: Heating of ore in absence of air below melting point.
   
   Moisture and CO₂ are removed.
   
   2Fe₂O3.₃H₂O 2Fe₂O₃ + 3H₂O
   
   FeCO₃ FeO + CO₂
    
3. Roasting: Heating of ore in excess of air below the melting point.
   
   Impurities (such as P, S, C, As, Sb etc.) are removed as their volatile oxides.
   
   S + O₂  SO₂
   4As + 3O₂2As₂O₃
   
   Ferrous oxide is oxidised to ferric oxide
   
   2FeO + O₂Fe₂O₃
    
4. Smelting: The calcined ore is mixed with limestone (a flux) and coke (a reductant) and smelted in blast furnace.