n-Hexane is a straight-chain saturated aliphatic hydrocarbon. It is obtained through the cracking and fractionation of crude oil. It appears as a colorless, oily liquid and is volatile where its vapour is heavier than air. It is insoluble in water but is soluble in chloroform, ethyl ether and ethanol. n-Hexane exists naturally as a hydrocarbon in petroleum and is one of the main constituents of petroleum ether and naphtha.
n-Hexane can be isolated from suitable sources (e.g., light gasoline or benzene, toluene, and xylene (BTX) or raffinates) by superfractionation or by molecular sieve separation. About 1-15% of n-hexane exists in straight-run gasoline, platinum reforming raffinate oil or wet natural gas. Current industrial production of hexane involves the separation of the raffinate from the platinum reforming unit (containing 11% to 13% of hexane). The raffinate is fractionated to remove light components and recombined to give a fraction containing 60-80% of n-hexane. Distillation, followed by catalyzed hydrogenation, would yield n-hexane suitable for sale.
It can be used as an extraction agent for cleaning in the electronics industry, the pharmaceutical industry and in the extraction of edible vegetable oil. It is also used for the extraction of oil fat contained in soybean, rice bran, cottonseed and spices.
Commercial grades of hexane are used as solvents for glues (rubber cement, adhesives), varnishes, and inks. As n-hexane is an organic solvent with good viscosity, it is commonly used in rubber food, pharmacy, perfume, footwear, tape, ball, grinding, leather, textile, furniture and paint industry as a dilution or cleaning solvent.
It can be used for the determination of moisture in methanol. It can be used for UV spectrum analysis, pesticide residue analysis, high performance liquid chromatography analysis (HPLC). It can be used as a standard for Gas Chromatographic (GC) analysis. It is also used as a substitute for mercury in thermometers. Hexane is also used as a cleaning agent (degreaser) in the printing industry and as the raw materials for the manufacture of polymers such as polypropylene and polyethylene. It is also a high-octane fuel.