Oleum: A vital raw material

Oleum, or fuming sulfuric acid, occurs in the industrial production of sulfuric acid. Sachtleben, one of the world's leading titanium dioxide manufacturers via the sulfate process, has one of Europe's largest sulfuric acid production plants. Due to the dissolved gaseous sulfur trioxide, which forms dense sulfuric acid mist in contact with airborne moisture ("humidity)", oleum "fumes" in contact with air. This translucent and colorless liquid is highly corrosive and reacts violently with water. The heat generated by this reaction is exploited in titanium dioxide production in order to heat the input products to the point at which the reaction of black ore and sulfuric acid starts. In addition, oleum is also used for the manufacture of surfactants and detergents, and for the production of hydrofluoric acid for the glass industry.