Question

Describe extraction of iron by pyrometallurgy.

Answer 1

The actual reductant is CO, which reduces Fe2O3 to give Fe(l) and CO2(g) (Equation 23.2.323.2.3); the CO2 is then reduced back to CO by reaction with excess carbon. As the ore, lime, and coke drop into the furnace any silicate minerals in the ore react with the lime to produce a low-melting mixture of calcium silicates called slag, which floats on top of the molten iron. Molten iron is then allowed to run out the bottom of the furnace, leaving the slag behind. Originally, the iron was collected in pools called pigs, which is the origin of the name pig iron.