Topic 4 - Reaction kinetics: an industrial case study

THE KEY REACTIONS IN THE CONTACT PROCESS

• Sulphur is burned in air to form sulphur dioxide: S+O2 = SO2
• The sulphur dioxide is then mixed with air and passed over a catalyst (usually vanadium pentoxide) where it reacts to form sulphur trioxide (reversible reaction):
• 2SO2(g) + O2(g) = 2SO3(g)
• The sulphur trioxide is reacted with sulphuric acid to form oleum, which is then diluted down with water to give concentrated sulphuric acid. It is not possible to react sulphur trioxide directly with water in the industrial process since it tends to form acidic mists.

MATERIALS USED

• It is helpful if the sulphur dioxide is as pure as possible, and for this reason it is…