Ethyl Acetate is a most familiar ester of ethanol which you can easily remember by its regular usage in our daily life. It is also called as ethyl ethanoate, commonly abbreviated EtOAc or EA. It is one of the ingredients responsible for the characteristic smell of a banana flower or overripe fruit has high levels of ethyl acetate.It is manufactured on a large scale for use as a solvent. Ethyl acetate can dissolve up to 3 per cent water and has a solubility of 8 per cent 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.
It is even much more familiar, being present as one of the ingredients of nail polish remover. Ethyl Acetate is also present in all beers as it a natural part of the fermentation process by yeasts. This flavour plays an importance part in the overall profile of the beer.
Generally speaking, ethyl acetate is a colourless liquid and has a characteristic sweet smell. It is used in glues, decaffeinating tea and coffee, and cigarettes.
It is also used in paints as an activator or hardener. Ethyl acetate is present in confectionery, perfumes.In perfumes, it evaporates quickly, leaving only the scent of the perfume on the skin.
Ethyl acetate is synthesised via the Fischer esterification reaction from ethanol and acetic acid, typically in the presence of an acid catalyst such as concentrated sulfuric acid. Fischer esterification is a special type of esterification by refluxing a carboxylic acid and an alcohol in the presence of an acid catalyst. The reaction was first described by Emil Fischer and Arthur Speier in 1895.
This mixture converts to the ester in about 65 synthesising yield at room temperature
CH3CH2OH + CH3COOH → CH3COOCH2CH3 + H2O
The reaction can be accelerated by acid catalysis and the equilibrium can be shifted to the right by removal of water. It is also prepared in industry using the Tishchenko reaction, by combining two equivalents of acetaldehyde in the presence of an alkoxide catalyst
2 CH3CHO → CH3COOCH2CH3
Silicotungstic acid is used to manufacture ethyl acetate by the alkylation of acetic acid by ethylene
C2H4 + CH3CO2H → CH3CO2C2H5
Ethyl acetate synthesizing by dehydrogenation of ethanol
A specialised industrial route entails the catalytic dehydrogenation of ethanol. This method is more cost effective than the esterification but is applied with surplus ethanol in a chemical plant. Typically, dehydrogenation is conducted with copper at an elevated temperature but below 250 °C.
It can also be prepared through Tishchenko reaction, by combining two equivalents of acetaldehyde in the presence of an alkoxide base as catalyst. This way is a commercial method of producing ethyl acetate.
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