Question -
Answer -
Sulphuric acid is manufactured bythe contact process. It involves the following steps:
Step (i):
Sulphur or sulphide ores areburnt in air to form SO2.
Step (ii):
By a reaction with oxygen, SO2 isconverted into SO3 in the presence of V2O5 asa catalyst.
Step (iii):
SO3 produced isabsorbed on H2SO4 to give H2S2O7 (oleum).
This oleum is then diluted toobtain H2SO4 of the desired concentration.
In practice, the plant isoperated at 2 bar (pressure) and 720 K (temperature). The sulphuric acid thusobtained is 96-98% pure.