Ethyl sulfate (IUPAC name: ethyl hydrogen sulfate), also known as sulfovinic acid, is an organic chemical compound used as an intermediate in the production of ethanol from ethylene. It is the ethyl ester of sulfuric acid.
History
This substance was studied contemporaneously with
diethyl ether by
Germany alchemy August Siegmund Frobenius in 1730,
subsequently by
France Fourcroy in 1797 and
Gay-Lussac in 1815.
[Fourcroy, A.F. and Vauquelin, L.N. (1797) "Sur l'action de l'acide sulfurique sur l'alcool et de la formation de l'éther" (On the action of sulfuric acid on alcohol and on the formation of ether), Annales de Chimie, 23 : 203-215.][Gay-Lussac, L.J. (1815) "Sur l'analyse de l'alcool et de l'éther sulfurique et sur les produits de la fermentation" (On the analysis of alcohol and sulfuric ether and on the products of fermentation), Annales de Chimie, 95 : 311-318.] Switzerland scientist Nicolas-Théodore de Saussure also studied it in 1807.
[Théodore de Saussure (1807) "Mémoire sur la composition de l'alcohol et de l'éther sulfurique," Journal de physique, de chimie, d'histoire naturelle et des arts, 64 : 316–354.] In 1827, French
chemist and
pharmacist Félix-Polydore Boullay (1806-1835) along with Jean-Baptiste André Dumas noted the role of ethyl sulfate in the preparation of
diethyl ether from
sulfuric acid and
ethanol.
[Dumas, J-B and Boullay, P. (1827) "Mémoire sur la formation de l'éther sulfurique," Annales de Chimie et de Physique, 36 : 294-316.] Further studies by the German chemist Eilhard Mitscherlich and the Swedish chemist Jöns Berzelius suggested sulfuric acid was acting as a
catalyst, this eventually led to the discovery of sulfovinic acid as an intermediate in the process.
[E. Mitscherlich (1834) "Ueber die Aetherbildung" (On the formation of ether), Annalen der Physik und Chemie, 31 (18) : 273-282.][J. J. Berzelius, Årsberättelsen om framsteg i fysik och kemi Annual, (Stockholm, Sweden: Royal Swedish Academy of Sciences, 1835). After reviewing Eilhard Mitscherlich's research on the formation of ether, Berzelius coins the word katalys (catalysis) on page 245 :
]Original: Jag skall derföre, för att begagna en i kemien välkänd härledning, kalla den kroppars katalytiska kraft, sönderdelning genom denna kraft katalys, likasom vi med ordet analys beteckna åtskiljandet af kroppars beståndsdelar medelst den vanliga kemiska frändskapen.
Translation: I shall, therefore, to employ a well-known derivation in chemistry, call the bodies i.e., the catalytic force and the decomposition of other bodies by this force catalysis, just as we signify by the word analysis the separation of the constituents of bodies by the usual chemical affinities.
The advent of
electrochemistry by
Italy physicist Alessandro Volta and
England chemist Humphry Davy in the 1800s confirmed ether and water were formed by the reaction of
stoichiometry amounts of sulfuric acid on ethanol and that sulfovinic acid was formed as an intermediate in the reaction.
Production
Ethanol was produced primarily by the sulfuric acid hydration process in which
ethylene is reacted with
sulfuric acid to produce ethyl sulfate followed by
hydrolysis,
but this method has been mostly replaced by direct hydration of ethylene.
Ethyl sulfate can be produced in a laboratory setting by reacting ethanol with sulfuric acid under a gentle boil, while keeping the reaction below 140 °C. The sulfuric acid must be added dropwise or the reaction must be actively cooled because the reaction itself is highly exothermic.
If the temperature exceeds 140 °C, the ethyl sulfate product tends to react with residual ethanol starting material, producing diethyl ether. If the temperature exceeds 170 °C in a considerable excess of sulfuric acid, the ethyl sulfate breaks down into ethylene and sulfuric acid.
Reactions
The mechanism of the formation of ethyl sulfate,
diethyl ether, and
ethylene is based on the reaction between ethanol and
sulfuric acid, which involves
protonation of the ethanolic oxygen to form the oxonium ion.
[
]
Ethyl sulfate accumulates in hair after chronic alcohol consumption and its detection can be used as a biomarker for alcohol consumption.
Salts
Ethyl sulfate can exist in salt forms, such as sodium ethyl sulfate, potassium ethyl sulfate, and calcium ethyl sulfate. The salt can be formed by adding the according carbonate, or bicarbonate salt. As an example, ethyl sulfate and potassium carbonate forms potassium ethyl sulfate and potassium bicarbonate.[
]
See also
