Isobutanol

Isobutanol (IUPAC nomenclature: 2-methyl-propan-1-ol; also known as 2-methylpropyl alcohol, among other names) is a colorless, flammable, organic compound with a characteristic smell. Its isomers are 1-butanol, 2-butanol and tert-butanol. It is classified as an alcohol and as such it is widely used as a solvent in chemical reactions, as well as being a useful starting material for organic synthesis.

Additional recommended knowledge

Daily Sensitivity Test

Essential Laboratory Skills Guide

Recognize and detect the effects of electrostatic charges on your balance

Isobutanol is produced naturally during the fermentation of carbohydrates. It may also be a by-product of the decay process of organic matter.

Applications

The main use of isobutanol is as starting material in the manufacture of isobutyl acetate, which is mostly used in the production of lacquer and similar coatings. Isobutyl acetate is also used in the food industry as flavouring agent.

Isobutanol is also used in the industrial synthesis of derivative esters. Isobutyl esters such as diisobutyl phthalate (DIBP) are used as plasticizer agents in plastics, rubbers and other dispersions.

Other applications of isobutanol include its use as a solvent in paint, varnish removers and inks. Its addition in small amounts into paints reduces their viscosity, improves brush flow, and retards the formation of oil residues (known as blush) on painted surfaces.

Minor uses include its inclusion as gasoline additive for spark-ignition engines where it helps to prevent carburettor icing, polishers and cleaners. It is used as chemical extractant in the production of organic compounds, and as mobile phase in thin layer chromatography.

Safety

Isobutanol is a volatile, flammable, liquid that should be stored and used in well-ventilated areas. It is moderately irritating to the skin and greatly irritating to the eyes, mucous membranes and respiratory tract. Exposure to high concentrations of its vapour can cause temporary narcosis.

Isobutanol is considered to be slightly toxic and it has been shown to cause liver damage in mice and humans. Ingestion may also lead to alcohol poisoning.

References

• Health and Safety Guide for Isobutanol. World Health Organisation, 1987. Last accessed October 5, 2005.