Dimethyl Ketone

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Dimethyl Ketone

OVERVIEW

Dimethyl ketone (DYE-meth-el KEY-tone) is a clear, colorless, highly volatile and highly flammable liquid with a characteristic sweet odor and taste. The compound is almost universally known in chemistry laboratories and industrial applications by its common name of acetone.

KEY FACTS

OTHER NAMES:

2-propanone; acetone

FORMULA:

CH3COCH3

ELEMENTS:

Carbon, hydrogen, oxygen

COMPOUND TYPE:

Ketone (organic)

STATE:

Liquid

MOLECULAR WEIGHT:

58.08 g/mol

MELTING POINT:

−94.7°C (−138°F)

BOILING POINT:

56.05°C (132.9°F)

SOLUBILITY:

Miscible with water, alcohol, ether, benzene, and chloroform

Acetone was apparently first prepared in 1610 by the French alchemist Jean Béguin (c. 1550–c. 1650). Béguin obtained acetone by heating lead acetate (also known as Saturn's salt) to a high temperature. He obtained a sweet-smelling, very flammable liquid that he named "burning spirit of Saturn." One of the first uses to which the substance was put was as a solvent in the extraction of the active constituents of opium. In 1833, the French chemist Antoine Bussy (1794–1882) gave the compound its modern name of acetone. The correct chemical formula for acetone was determined independently in 1832 by the French chemist Jean Baptiste André Dumas (1800–1884) and the German chemist Justus von Liebig (1803–1873).

HOW IT IS MADE

Most of the acetone produced today is made by one of four methods:

  • In the Hock process, cumene [C6H5CH(CH3)2] is first oxidized to produce cumene hydroperoxide [C6H5C(CH3)2COOH], which is then reduced to produce acetone and phenol (C6H5OH); or
  • Isopropyl alcohol (2-propanol; CH3CHOHCH3) is oxidized over a catalyst to obtained acetone; or
  • Butane (C4H10) is oxidized to obtain acetone; or
  • Acetone is obtained as a by-product of the manufacture of glycerol [C3H5(OH)3].

COMMON USES AND POTENTIAL HAZARDS

Acetone's primary applications are based on its ability to dissolve such a wide array of organic substances. It is used as a solvent for paints, varnishes, lacquers, inks, glues, rubber cements, fats, oils, waxes, and various types of rubber and plastics. It is perhaps best known to the average person as the primary ingredient in nail polish remover. The largest single use of the compound is as a raw material in the manufacture of other organic chemicals, such as chloroform, acetic acid, iodoform, bromoform, isoprene, rayon, and photographic film. It also finds application in storing acetylene gas (because it absorbs up to 24 times its own weight of the gas), to clean and dry chemical equipment and electronic parts, and for the extraction of components of plant and animal tissues.

The primary safety concern about acetone is its extreme flammability. Workers who handle the compound must use great care to prevent its coming into contact or even being in the vicinity of open flames. Under the proper conditions, acetone is also explosive. Exposure of the skin, eyes, and respiratory system to acetone may produce mild symptoms, such as dizziness, headaches, and disorientation and irritation of the eyes and skin. Such conditions are rare, however, and no long-term health effects of the compound have as yet been discovered.

Words to Know

MISCIBLE
able to be mixed; especially applies to the mixing of one liquid with another.
VOLATILE
A term describing a liquid that can be easily changed to gas.

FOR FURTHER INFORMATION

"Acetone." International Labour Organization. http://www.ilo.org/public/english/protection/safework/cis/products/icsc/dtasht/_icsc00/icsc0087.htm (accessed on October 7, 2005).

"Safety (MSDS) data for propanone." Physical and Theoretical Chemistry Lab Safety. http://ptcl.chem.ox.ac.uk/MSDS/PR/propanone.html (accessed on October 7, 2005).

"Toxicological Review of Acetone." Environmental Protection Agency. http://www.epa.gov/iris/toxreviews/0128-tr.pdf (accessed on October 7, 2005).