Oleum is a cloudy, gray, fuming, oily, corrosive liquid with a sharp, penetrating odor. When Oleum comes into contact with air following a spill, it releases Sulfur Trioxide. Sulfur Trioxide is a white gas having the appearance of fog. It also has a sharp, penetrating odor that is detectable at low concentrations. Because of the tendency to liberate Sulfur Trioxide on contact with air, Oleum is also known as “fuming Sulfuric Acid”.
Oleum is made by dissolving Sulfur Trioxide into Sulfuric Acid. Sulfur Trioxide is made from Sulfur Dioxide in the presence of a catalyst.
It is used in the oil refining process to make crude oil distillates into higher quality materials. Manufacture of soap Manufacture of high purity Sulfuric Acid for the electronic industry Manufacture of catalyst used in production of Sulfuric Acid.