Abstract:
All commercial sulphur sources containing more than 99.5 percent sulphur are
suitable as raw materials. The sulphur is melted and burned with dried air
to give a gas mixture containing 8 to 12 percent S02 by volume, the
combustion temperature is held at about 800'C. After addition of more
air, the S'2 is oxidised to S'3 over a vanadium catalyst. The S03 is
absorbed in sulphuric acid of 98.3 percent H2S04 and converted with its
water content into H2S04. Absorption and drying of the process air take
place in packed towers where the gas are sprayed in counter-current with
cooled concentrated sulphuric acid. The entire sulphuric acid plant
operates with yields of more than 97.8 percent.