Butyl Acetate

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Butyl Acetate

OVERVIEW

Butyl acetate (BYOO-til AS-uh-tate) exists in three isomeric forms. Isomers are two or more forms of a chemical compound with the same molecular formula, but different structural formulas and different chemical and physical properties. Their names and synonyms are as follows: n-butyl acetate is known as butyl ester, or butyl ethanoate; sec-butyl acetate is called 1-methylpropyl ester and acetic acid sec-butyl ester; and tert-butyl acetate is known by 1,1,-dimethylethyl ester or acetic acid, tert-butyl ester. The expanded chemical formulas for the forms are slightly different: n-butyl acetate, CH3COOCH2CH2CH2CH3; sec-butyl acetate, CH3COOCH(CH3)(C2H5); and tert-butyl acetate, CH3COOC(CH3)3.

KEY FACTS

OTHER NAMES:

Three forms exist; see Overview

FORMULA:

C6H12O2; see Overview for expanded formulas

ELEMENTS:

Carbon, hydrogen, oxygen

COMPOUND TYPE:

Carboxylic acids (organic)

STATE:

Liquid

MOLECULAR WEIGHT:

116.16 g/mol

MELTING POINT:

−98.9°C (−146°F) to −78°C (−108°F)

BOILING POINT:

95.1°C (203°F) to 126.1°C (259.0°F)

SOLUBILITY:

Insoluble or slightly soluble in water; soluble in alcohol and ether

About 100,000 kilograms (250,000 pounds) of the n-butyl isomer, the most popular, is produced each year in the United States. By far the most common use of the compound (and the isomers) is as an industrial solvent, with about 90 percent of total output going for this use.

HOW IT IS MADE

All three isomers of butyl acetate are made by reacting acetic acid (CH3COOH) with the appropriate butyl alcohol (n-butyl alcohol, sec-butyl alcohol, or tert-butyl alcohol, respectively).

COMMON USES AND POTENTIAL HAZARDS

The primary use of all three isomers of butyl acetate is as a solvent in the production of lacquers and paints; photographic film; resins; and coatings for furniture, fixtures, containers, and automobiles. Since the 1990s, these compounds have been substituted for other solvents that are considered hazardous environmental pollutants.

Other uses of the isomers are as follows:

  • n-butyl acetate: as an odor enhancer in perfumes; in the synthesis of synthetics flavors, pharmaceuticals, and other organic compounds;
  • sec-butyl acetate: as a thinner for nail enamels and a solvent for leather finishes;
  • tert-butyl acetate: as a gasoline additive.

Interesting Facts

Scientists have discovered that the butyl acetates are present in the so-called alarm pheromones secreted by animals, particularly insects. An alarm pheromone is a chemical secreted when an animal is under attack. It alerts other animals in the neighborhood to the attack and "tells" them to respond to the attack that has been detected.

Words to Know

ISOMER
One of two or more forms of a chemical compound with the same molecular formula, but different structural formulas and different chemical and physical properties.
SOLVENT
A substance that is able to dissolve one or more other substances

Relatively little data are available on the health effects of exposure to the isomers of butyl acetate. The chemical is known to cause skin rash, respiratory problems, and burning of the eyes upon contact. And by comparing it with other similar organic compounds, the assumption is made that long-term exposure to high concentrations would result in damage to the nervous system. Since most people do not encounter butyl acetate in the pure form, these risks are minimal. Only workers in one of the fields in which the chemical is used need take special precautions to use care in working with the amyl acetates.

FOR FURTHER INFORMATION

"Global Ethyl, Butyl Acetate Demand Expected to Rebound." The Oil and Gas Journal (April 24, 2000): 27.

"n-butyl acetate." New Jersey Department of Health and Senior Services. http://www.state.nj.us/health/eoh/rtkweb/1329.pdf (accessed on September 22, 2005).

"Occupational Safety and Health Guideline for tert-butyl Acetate." Occupational Health and Safety Administration. http://www.osha.gov/SLTC/healthguidelines/tertbutylacetate/recognition.html (accessed on September 22, 2005).

"sec-butyl acetate." Scorecard: The Pollution Information Site. http://www.scorecard.org/chemical-profiles/summary.tcl?edf_substance_id=105%2d46%2d4 (accessed on September 22, 2005).