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Information about Ethyl Acetate











Ethyl acetate
Other namesethyl ester,
ethyl acetate,
acetic ester,
ester of ethanol
Identifiers
CAS number141-78-6
RTECS numberAH5425000
SMILESCCOC(C)=O
Properties
Molecular formulaC4H8O2
Molar mass88.105 g/mol
Appearancecolorless liquid
Density0.897 g/cm³, liquid
Melting point −83.6 °C (189.55 K)
Boiling point 77.1 °C (350.25 K)
Solubility in water8.3 g/100 mL (20 °C)
Solubility in ethanol,
acetone, diethyl ether,
benzene		Miscible
Refractive index (nD)1.3720
Viscosity0.426 cP at 25 °C
Structure
Dipole moment1.78 D
Hazards
MSDSExternal MSDS
Main hazardsFlammable (F),
Irritant (Xi)
NFPA 704
3
1
0
 
R-phrasesR11, R36, R66, R67
S-phrasesS16, S26, S33
Flash point−4 °C
Related Compounds
Related carboxylate estersMethyl acetate,
Butyl acetate
Related compoundsAcetic acid,
ethanol
Supplementary data page
Structure and
properties		n, εr, etc.
Thermodynamic
data		Phase behaviour
Solid, liquid, gas
Spectral dataUV, IR, NMR, MS
Except where noted otherwise, data are given for
materials in their standard state
(at 25 C, 100 kPa)


Ethyl acetate is the organic compound with the formula CH3CH2OC(O)CH3. This colorless liquid has a characteristic, not unpleasant smell (similar to pear drops) like certain glues or nail polish removers, in which it is used. As the ester derived from ethanol and acetic acid, thus commonly abbreviated EtOAc, it is manufactured on a large scale for use as a solvent.

Properties

Ethyl acetate is a moderately polar solvent that has the advantages of being volatile, relatively non-toxic, and non-hygroscopic. It is a weak hydrogen bond acceptor, and is not a donor due to the lack of an acidic proton (one directly bonded to an electronegative atom such as fluorine, oxygen, or nitrogen). Ethyl acetate can dissolve up to 3% water and has a solubility of 8% in water at room temperature. At elevated temperature its solubility in water is higher. It is unstable in the presence of strong aqueous bases and acids.

Uses and occurrence

Ethyl acetate is a moderately polar solvent that has the advantages of being volatile, relatively non-toxic, and non-hygroscopic. It is a weak hydrogen bond acceptor, and is not a donor due to the lack of an acidic proton (one directly bonded to an electronegative atom such as fluorine, oxygen, or nitrogen). Ethyl acetate can dissolve up to 3% water and has a solubility of 8% in water at room temperature. At elevated temperature its solubility in water is higher. It is unstable in the presence of strong aqueous bases and acids. Ethyl acetate is widely employed as a solvent for nail varnishes and nail varnish removers. Industrially it is used to decaffeinate coffee beans and tea leaves. In chemistry, it is often mixed with a non-polar solvent such as hexanes as a chromatography solvent. It is also used as a solvent for extractions. It is rarely used as a reaction mixture due to the weakness of the ester linkage — it hydrolyzes in the presence of strong acids and bases to give acetic acid and ethanol.

Ethyl acetate is also present in confectionery, perfumes, and fruits. It is used in perfumes because it evaporates at a fast rate, leaving but the scent of the perfume on the skin. It also confers a fruity smell, as do most esters. It is also used in paints as an activator or hardener.

Occurrence in wines

Ethyl acetate is present in wines. It may be considered a contaminant at too high concentrations, as typically occurs when wine is exposed to air for a prolonged period. When present at too high concentration in wine, it is regarded as an off-flavour.

Other uses

In the field of entomology, ethyl acetate is an effective poison for use in insect collecting and study. In a killing jar charged with ethyl acetate, the vapors will kill the collected (usually adult) insect quickly without destroying it. Because it is not hygroscopic, ethyl acetate also keeps the insect soft enough to allow proper mounting suitable for a collection.

Synthesis

Ethyl acetate is synthesized via the Fischer esterification reaction from acetic acid and ethanol, typically in the presence of an acid catalyst such as sulfuric acid.
CH3CH2OH + CH3COOH → CH3COOCH2CH3 + H2O

Industrial synthesis

Industrially, ethyl acetate can be produced by the catalytic oxidization of ethanol. For cost reasons, this method is primarily applied to conversion of surplus ethanol feedstock as opposed to predetermined generation on an industrial scale. In addition, it is commonly accepted as far less practical and less cost effective.

Catalysts for hydrogenation include copper, operating at an elevated temperature but below 250 °C. The copper may have its surface area increased by depositing it on zinc, promoting the the growth of snowflake, fractal like, structures. This surface area can be again increased by deposition onto a zeolite, typically ZSM-5. Traces of rare earth metals or alkalies, such as that of sodium and potassium, have also been found to be beneficial to the process. Byproducts of hydrogenation include diethyl ether (thought to primarily arise due to aluminum sites in the catalyst), acetaldehyde, acetaldehyde aldol products, higher esters and ketones. Acetaldehyde and MEK complicate conversion and purification as ethanol forms an azeotrope with water, as does ethyl acetate with ethanol and water and MEK with both ethanol and the acetate. To obtain a high purity product, these azeotropes must be "broken", and this can be achieved by making use of pressure swing distillation.

The composition of the distillate removed from the conversion products is biased towards acetate at atmospheric pressure and ethanol at increased pressure. First, the raw product is fed into a high pressure column where the bulk of the contaminating ethanol is removed. By then feeding the ethanol depleted distillate into a low pressure column, the acetate can be removed from the remaining ethanol azeotrope.

MEK forms during the conversion process from 2-butanol. The latter fails to form an azeotrope with the acetate and so MEK can be removed by hydrogenation of the contaminated product over nickel and further distillation to strip away 2-butanol. This provides the simultaneous benefit of removing the acetylaldehyde contaminant by returning it to an ethanol form and is easily accomplished as hydrogen is a byproduct of the initial dehydrogenation process.

It may also be possible to break the azeotropes with the use of membrane distillation, molecular sieves, an entrainer or absorption medium.

The distilled ethanol and rehydrogenated contaminants can then be recycled into the raw feedstock.

Reactions

Ethyl acetate can be hydrolyzed in acid or basic conditions to regain acetic acid and ethanol. The use of an acid catalyst such as sulfuric acid gives poor yields due to it being an equilibrium — the reverse reaction of the Fischer esterification.

To obtain high yields, it is preferable to use a stoichiometric amount of strong base, such as sodium hydroxide. This reaction gives ethanol and sodium acetate, which is not able to react with ethanol any longer:

CH3CO2C2H5 + NaOH → C2H5OH + CH3CO2Na

See also

External links

References

CAS registry numbers are unique numerical identifiers for chemical compounds, polymers, biological sequences, mixtures and alloys. They are also referred to as CAS numbers, CAS RNs or CAS #s.
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smiles

File extension: .smi
Type of format: chemical file format

The simplified molecular input line entry specification or SMILES
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A chemical formula is a concise way of expressing information about the atoms that constitute a particular chemical compound. A chemical formula is also a short way of showing how a chemical reaction occurs.
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Molar mass, symbol M,[1] is the mass of one mole of a substance (chemical element or chemical compound).[2] It is a physical property which is characteristic of each pure substance.
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In physics, density is mass m per unit volume V—how heavy something is compared to its size. A small, heavy object, such as a rock or a lump of lead, is denser than a lighter object of the same size or a larger object of the same weight, such as pieces of
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The melting point of a crystalline solid is the temperature range at which it changes state from solid to liquid. Although the phrase would suggest a specific temperature and is commonly and incorrectly used as such in most textbooks and literature, most crystalline compounds
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boiling point of a liquid is the temperature at which the vapor pressure of the liquid equals the environmental pressure surrounding the liquid.[1][2][3][4]
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Solubility is a physical property referring to the ability for a given substance, the solute, to dissolve in a solvent.[1] It is measured in terms of the maximum amount of solute dissolved in a solvent at equilibrium. The resulting solution is called a saturated solution.
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Water is a common chemical substance that is essential to all known forms of life.[1] In typical usage, water refers only to its liquid form or state, but the substance also has a solid state, ice, and a gaseous state, water vapor.
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Solubility is a physical property referring to the ability for a given substance, the solute, to dissolve in a solvent.[1] It is measured in terms of the maximum amount of solute dissolved in a solvent at equilibrium. The resulting solution is called a saturated solution.
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Ethanol, also known as ethyl alcohol, drinking alcohol or grain alcohol, is a flammable, colorless, slightly toxic chemical compound, and is best known as the alcohol found in alcoholic beverages.
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The chemical compound acetone (also known as propanone, dimethyl ketone, 2-propanone, propan-2-one and β-ketopropane) is the simplest representative of the ketones.
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Diethyl ether, also known as ether and ethoxyethane, is a clear, colorless, and highly flammable liquid with a low boiling point and a characteristic smell. It is the most common member of a class of chemical compounds known generically as ethers.
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Benzene, or Benzol (see also Benzine) is an organic chemical compound with the formula C6H6. It is sometimes abbreviated Ph–H. Benzene is a colorless and inflammable liquid with a sweet smell and a relatively high melting point.
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The refractive index (or index of refraction) of a medium is a measure for how much the speed of light (or other waves such as sound waves) is reduced inside the medium. For example, typical glass has a refractive index of 1.
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Viscosity is a measure of the resistance of a fluid to deform under either shear stress or extensional stress. It is commonly perceived as "thickness", or resistance to flow.
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The poise (symbol P; IPA: /pwɑːz/) is the unit of dynamic viscosity in the centimetre gram second system of units. It is named after Jean Louis Marie Poiseuille.
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The debye (symbol: D) is a non-SI and non-CGS unit of electrical dipole moment. It is defined as 10-18 statcoulomb centimeter (or 10-20 esu m). In SI units, 1 D equals 3.33564*10-30 coulomb meter. It is named after the physicist Peter J.
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material safety data sheet (MSDS) is a form containing data regarding the properties of a particular substance. An important component of product stewardship and workplace safety, it is intended to provide workers and emergency personnel with procedures for handling or
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Occupational safety and health (OSH) is a cross-disciplinary area concerned with protecting the safety, health and welfare of people engaged in work or employment. As a secondary effect, OSH may also protect co-workers, family members, employers, customers, suppliers, nearby
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NFPA 704 is a standard maintained by the U.S. National Fire Protection Association. It defines the colloquial "fire diamond" used by emergency personnel to quickly and easily identify the risks posed by nearby hazardous materials.
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R-phrases (short for Risk Phrases) are defined in Annex III of European Union Directive 67/548/EEC: Nature of special risks attributed to dangerous substances and preparations.
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S-phrases are defined in Annex IV of European Union Directive 67/548/EEC: Safety advice concerning dangerous substances and preparations. The list was consolidated and republished in Directive 2001/59/EC , where translations into other EU languages may be found.
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The flash point of a flammable liquid is the lowest temperature at which it can form an ignitable mixture in air. At this temperature the vapor may cease to burn when the source of ignition is removed.
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A carboxylate ester is an ester where the parent acid is a carboxylic acid.

Most typically, the term 'ester' means a carboxylate ester. Although accurately, the acid part of an ester can be any acid.

For one, methyl formate is a carboxylate ester.
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Methyl acetate, also known as acetic acid methyl ester or methyl ethanoate, is a clear, flammable liquid with a characteristic, not unpleasant smell like certain glues or nail polish removers.
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The chemical compound n-butyl acetate, also known as butyl ethanoate, is commonly used as a solvent in the production of lacquers and other products. It is also used as a synthetic fruit flavoring in foods such as candy, ice cream, cheeses, and baked goods.
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Acetic acid, also known as ethanoic acid, is an organic chemical compound best recognized for giving vinegar its sour taste and pungent smell. Its structural formula is represented as CH3COOH.
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Ethanol, also known as ethyl alcohol, drinking alcohol or grain alcohol, is a flammable, colorless, slightly toxic chemical compound, and is best known as the alcohol found in alcoholic beverages.
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P in mm Hg 1 10 40 100 400 760 1520 3800 7600 15200 30400 45600
T in °C –43.4 –13.5 9.1 27.0 59.0 77.1 100.6 136.6 169.7 209.5  —  ? Table data obtained from CRC Handbook of Chemistry and Physics 44th ed.
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