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| Electrometallurgy |
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| "The extraction of certain metals from their ores by the process of electrolysis is called electrometallurgy." |
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| Certain metal oxides are highly stable and so cannot be reduced by conventional reducing agents like coke, carbon monoxide or hydrogen. They are extracted from their oxides or salts by the electrolysis in fused state. For e.g., metals like aluminium, sodium, potassium, magnesium, titanium, calcium etc. are extracted by this method. |
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| a) Electrometallurgy of Aluminium |
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 Electrolyte - Mixture of alumina (from ore), cryolite (Na3AlF6) and fluorspar (CaF2) in fused state. |
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Cathode - Gas carbon lining. |
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Anode - Graphite |
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Dissociation of Alumina - |
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| b) Extraction of sodium - from sodium chloride (in fused state) |
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| Dissociation of sodium chloride occurs as . |
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| Similar reactions take place in electrolysis of fused calcium chloride and potassium bromide. |
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