Toluene

anic compounds, as a solvent for paints, lacquers, gums, resins, thinner for inks, perfumes, dyes, in the extraction of various principles from plants, as gasoline additive.

The major use of toluene is as a mixture added to gasoline to improve octane ratings. Toluene is also used to produce benzene and as a solvent in paints, coatings, synthetic fragrances, adhesives, inks, and cleaning agents.

Industrial uses: Diluent, Waterproofing agent, Catalyst, Reducing agent, Sealant (barrier), Plasticizer, Laboratory chemicals.

Consumer uses: Adhesion/cohesion promoter, Intermediate, Sealant (barrier), Catalyst, Corrosion inhibitor, Plasticizer, Fuel agents.

Use classes: Hydrocarbons, Volatile organic compounds, Solvents, Cosmetics, Animal Drugs.

An important aspect of the extraction of toluene is the fact that the pyrolysis products (from steam cracking, coking, etc.) must be hydrogenated before pure toluene can be extracted. The unsaturated components are converted to saturated ones and the heteroatoms such as sulfur, nitrogen, and oxygen are removed. In the case of reformates such pretreatment is usually unnecessary. For the separation of toluene from other components within the same boiling range several methods are available, depending on quality requirements. Fine fractionation is now suitable only for the production of toluene with lower purity, and involves significant losses in fores and tails. Azeotropic distillation uses entrainers, such as methanol, to separate toluene from nonaromatics, a nonaromatics - methanol fraction with a lower bp than the methanol - toluene azeotrope distills at the column head, while pure toluene is removed from its base. Methanol is recovered from the distillate by washing with water.