Worlds of David Darling
Encyclopedia of Science
   
Home > Encyclopedia of Science

sulfuric acid (H2SO4)





sulfuric acid manufacture
To make sulfuric acid, liquid sulfur is blown (1) into a burner (3), also fed with air (2), forming sulfur dioxide . This passes through the filter (4) to the cooling tower (5). In the washing (6) it is washed with water then dried in a packed tower (7) of Raschig rings by means of 98% sulfuric acid entering at 8 and leaving at 9. In the converter (10) the dry sulfur dioxide reacts with oxygen (11), is cooled (12) and the resultant sulfur dioxide is absorbed in 98% sulfuric acid (13) to yield oleum (14). This is diluted (15) with sulfuric acid (16) to produce 98% sulfuric acid (17).
Formerly known as oil of vitriol, a highly corrosive, dense, oily liquid, colorless to dark brown depending on its purity. Sulfuric acid (H2SO4) is an oxidizing agent, reacting with metals, sulfur, and carbon on heating, and is a powerful dehydrating agent. In aqueous solution it is a strong acid, and reacts with bases and most metals to give sulfates. Fuming sulfuring acid, or oleum, is 100% sulfuric acid containing dissolved sulfur trioxide; it is used to manufacture sulfonic acid.

Sulfuric acid is used to manufacture a variety of chemicals including fertilizers, dyestuffs, paints, detergents, and explosives. It is itself manufactured industrially by the oxidation of sulfur dioxide in the contact process.


relative density 1.84
melting point 10.3°C (50.5°F)
boiling point 330°C (626°F)


Related category

   • INORGANIC CHEMISTRY