Question

Mention the conditions to maximize the yield of H₂SO₄ by contact process.

Answer 1

• In the contact process of the manufacture of sulphuric acid, SO₂ is oxidised to SO₃ by heating the mixture on the heterogeneous catalyst V₂O₅.

 2SO_2(g) + O_2(g) ⇌ 2SO_3(g) ΔH = – 196.6 kJ

• The forward reaction is exothermic and there is a decrease in number of moles and volume.
• The optimum conditions to maximise the yield of H₂SO₄ are pressure of 2 bar and temperature around 720 K.