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

Figure 1: All the equations you need to know

Figure 2

Coke, which contains carbon, burns in air to produce heat (and CO2), meaning that it is exothermic. The CO2 reacts with MORE C to form carbon monoxide, which is needed to reduce iron oxide.

Limestone, which contains calcium carbonate, is used to get rid of impurities: it reacts with them to produce molten slag, which can be used to build roads.

Hot air is needed so the coke can burn.

Because carbon is higher up in the reactivity series than iron, it displaces iron in the reaction Fe₂O₃ + 3CO  →   2Fe + 3CO₂

In that reaction, iron oxide is reduced to iron and carbon monoxide is oxidised to produce carbon dioxide.