Acetaldehyde, also called ethanal, is the simplest aldehyde (CH3CHO). Acetaldehyde is a colourless and volatile liquid made by the catalytic oxidation of ethanol, with a sharp and fruity odour.It is widely used industrially as a chemical intermediate.Acetaldehyde is also a metabolite of sugars and ethanol in humans,is found naturally in the environment, and is a product of biomass combustion.
Acetaldehyde is primarily used as an intermediate in the manufacture of a range of chemicals, perfumes, aniline dyes, plastics and synthetic rubber and in some fuel compounds. Acetaldehyde is an important reagent used in the manufacture of dyes, plastics, and many other organic chemicals.
In the presence of acids it forms the cyclic polymers paraldehyde (CH3CHO)3, and metaldehyde (CH3CHO)4. The former is used as a hypnotic, and the latter as a solid fuel for portable stoves and as a poison for snails and slugs.
Acetaldehyde is also used in the manufacture of disinfectants, drugs, perfumes, explosives, lacquers and varnishes, photographic chemicals, phenolic and urea resins, rubber accelerators and antioxidants, and room air deodourizers. It is also used as a synthetic flavouring substance, food preservative and as a fragrance.
figure 1 Acetaldehyde 2d structural formula
