Thursday, 16 May 2013

5.4 describe and explain the main reactions involved in the extraction of iron from iron ore (haematite), using coke, limestone and air in a blast furnace

Iron is displaced from its ore (haematite) by carbon (from coke):
2Fe2O3 + 3C > 4Fe + 3CO2
It is also displaced by carbon monoxide
Fe2O3 + 3CO > 2Fe + 3CO2
Limestone reacts with impurities to from 'slag' which is tapped off.
Air allows burning to take place (of coke.)

chemguide

13 comments:

  1. Hey is that the only equation we need to know when it comes to this topic? As in do we not need to know the equation of formation of slag?

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    1. As far as I can remember its just this :)

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  2. the equation is wrong
    it's
    2Fe2O3+3CO>4Fe+3CO2

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    1. no...ur one is not balanced

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    2. it has 9 oxygen on the reactant side and only 6 on the products. did 3 just disappear?XD

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  3. Yeah it's wrong.. Coke burns in oxygen (from air) forming CO2
    this reaction is exothermic.. CO2 rises up in the furnace combining with the remaining coke forming CO which is the reducing agent (reduces iron oxide to iron) Fe2O3+3CO->2Fe+3Co2

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  4. I think both our equations are right, both carbon and carbon monoxide can displace oxygen in the blast furnace. I will add your guys one to the post :)

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  5. WHY CANT ALUMINIUM BE EXTRACTED USING COKE IN A BLAST FURNACE?

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    1. Because aluminium is more reactive than carbon, therefore coke (carbon) will not displace it in the reaction. (See 5.2 - extraction of aluminium through electrolysis)

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  6. Don't we need to learn these aswell?:

    2C + 02 -> 2CO (Coke)
    Fe2O3 + 3CO -> 2Fe + 3CO2 (Iron ore)
    CaCO3 -> CaO + CO2 (Limestone thermally decomposes)
    CaO + SiO2 -> CaSiO3 (Forms Slag)

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    1. You have the right set of equations, stick with those and ignore the ones above

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  7. Iron is displaced from haematite by carbon in hotter parts of the furnace-
    FE2O3(s)+3C(s)-> 2Fe(l)+3CO(g)- forms carbon monoxide not dioxide

    Carbon monoxide s the main reducing agent- especially in cooler parts (provided it is haematite- Fe2O3)
    -Fe2O3+3CO-> 2Fe(l) + 3CO2(g)

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