n-Hexane

n-Hexane is a chain-like hydrocarbon from the alkane group with the chemical formula C₆H₁₄. It is the unbranched representative and technically the most important of the five hexane isomers.

Physical Parameter

n-Hexane is almost insoluble in water, but shows very good solubility or unlimited miscibility with many organic solvents such as ethanol, ethers, esters, white spirit, aromatics or chlorinated hydrocarbons.

Application

Like all alkanes (paraffins, saturated hydrocarbons), n-hexane is a very good solvent for non-polar substances, fats and oils. It is used on a large scale for the extraction of oils and fats from nuts, seeds and fruits. It is also widely used for the extraction and work-up of natural products from plant components.

For many air-sensitive organometallic compounds and catalysts such as butyllithium and tert-butyllithium, n-hexane is an important solvent. Butyllithium and related molecules are extremely strong bases and are used in the synthesis of fine chemicals.

Some polymers and elastomers are produced in n-hexane as a solvent. This makes use of the properties that n-hexane is still liquid even at very low temperatures, dissolves the monomers, but the polymer can be easily precipitated and separated from the solution. In addition, n-hexane is chemically inert, so it does not participate in the reaction process.

Today, polyethylene is still partly produced in the so-called slurry process with n-hexane as solvent. 

Butyl rubber (IIP, isobutene-isoprene rubber, also outdated PIBI) and polybutadiene rubber (BR) are produced by anionic chain polymerization at very low temperature and with butyllithium as starter.

• Solvent for non-polar substances
• Extraction of oils and fats
• Extraction of natural substances
• Solvent for butyllithium, tert-butyllithium and catalysts
• Production of polymers (polyethylene, PE) and elastomers (synthetic rubbers)

Synonyms: Hexane