Sulfolane is a colorless oily liquid with a weak oily odor. Solidifies (freezing point is 79° F) and sinks on first contact with water, then mixes with water. (USCG, 1999) Sulfolane is a member of the class of tetrahydrothiophenes that is tetrahydrothiophene in which the sulfur has been oxidised to give the corresponding sulfone. A colourless, high-boiling (285℃) liquid that is miscible with both water and hydrocarbons, it is used as an industrial solvent, particularly for the purification of hydrocarbon mixtures by liquid-vapour extraction. It has a role as a polar aprotic solvent. It is a sulfone and a member of tetrahydrothiophenes. It derives from a hydride of a tetrahydrothiophene.

With high thermal stability and stability against acids and alkalis, it is an excellent solvent.It can be used to extract aromatic hydrocarbons from aliphatic hydrocarbons and remove acid gases from gas mixtures.Sulfolane can be used as a solvent for polymers such as polyacrylonitrile, acrylonitrile copolymers, polyvinyl fluoride, etc., for spinning and film production.It can also serve as a plasticizer for cellulose ethers, polyvinyl alcohol, polyethylene, polyvinyl chloride, polyamides, etc., and as an additive for acrylic fiber spinning.Additionally, it can be used for the separation of fatty acids and the extraction of non-cellulosic components from wood.Due to its high boiling point, good thermal stability and non-corrosiveness, sulfolane can be used as a condenser medium.When added to press oil, it can improve corrosion resistance, flame resistance, thermal stability, viscosity and other properties.