Esterification . A wide variety of solvents , monomers , medicines, perfumes and explosives are made from nitric acid esters .
Summary
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- 1 Compounds obtained by esterification reactions
- 2 Ester Manufacturing Process
- 3 Obtaining ethyl acetate
- 4 Obtaining amyl, butyl and isopropyl acetates
- 5 most important vinyl esters
- 6 Sources
Compounds obtained by esterification reactions
As an example of compounds that can be obtained by means of the esterification reactions, mention may be made of ethyl acetate , n-butylacetate , iso-butylacetate , glycerol tri-nitrate , penta-erythritol tetra-nitrate (TNPE), di-nitrate glycol and cellulose nitrate .
Ester Manufacturing Process
The manufacture of an ester is a relatively simple process in which an alcohol and an acid are put to heat together, in the presence of sulfuric acid as catalyst, and the reaction is completed by removing the products as they are formed (usually by distillation), while an excess of one of the reagents is used.
Obtaining ethyl acetate
In the case of obtaining ethyl acetate, the esterification takes place in a column, in which alcohol is added to the condensed liquid that comes out of the top, in order to wash the alcohol, which is then purified by distillation and returned to the column to react again.
Obtaining amyl, butyl and isopropyl acetates
The amyl, butyl and isopropyl acetates are all obtained using acetic acid and the appropriate alcohols. All of these esters are useful solvents and their low evaporation rate (compared to acetone or ethyl acetate) prevents the surface of the ester from falling below its dew point, which will cause film condensation and the appearance of a mottled surface (redness). Other esters of importance in the perfumery field and as plasticizers are also used, including methylsalicylate, methyl anthranilate, di-ethylphthalate, di-butylphthalate and di-2-ethylhexylphthalate. The unsaturated vinylesters used in the polymerization reactions are manufactured through the esterification of the olefins.
Major vinyl esters
The most important vinyl esters are: vinyl acetate, vinyl chloride, acrylonitrile and vinyl fluoride. The addition reaction can be carried out either in the liquid phase, the vapor phase or both, depending on the properties of the acid. Some care should be taken in reducing the polymerization of the vinyl ester produced. Esters of allyl alcohol, for example, di-allylphthalate, are used as bifunctional polymerization monomers and can be prepared by simple esterification of the phthalic anhydride with allyl alcohol. Various acrylic esters, such as ethyl- or methyl-acrylates, are also widely used and can be obtained from acrylic acid and the appropriate alcohol. The esters obtained are more volatile than the corresponding acids.