Sulfolane, also known as tetrahydrothiophene-1,1-dioxide, has the chemical formula C4H8O2S. It is a colorless transparent liquid and an excellent aprotic polar solvent, miscible with water, acetone, toluene, etc. It is also an ideal solvent in the petrochemical industry for aromatic extraction processes.

1. Appearance: Colorless transparent liquid.

2. Boiling point (°C, 101.3 kPa): 287.3

3. Melting point (°C): 28.45

4. Relative density (g/mL, 30/4°C): 1.2614

5. Relative vapor density (g/mL, air=1): 4.2

6. Refractive index (30°C): 1.4820

7. Viscosity (mPa·s, 30°C): 10.286

8. Flash point (°C): 166


Uses of Sulfolane: Due to its high thermal stability and stability to acids and bases, it is an excellent solvent. It can be used to extract aromatic hydrocarbons from aliphatic hydrocarbons and remove acidic gases from gas mixtures. Sulfolane can be used as a solvent for high molecular compounds such as polyacrylonitrile, acrylonitrile copolymers, polyvinyl fluoride, etc., for spinning and film manufacturing. It is also used as a plasticizer for cellulose ethers, polyvinyl alcohol, polyethylene, polyvinyl chloride, polyamides, etc., and as an additive in 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 carrier. When added to compressor oils, it improves properties such as corrosion resistance, flame resistance, thermal stability, and viscosity.