In this way diethyl ether is very similar to one of its precursors, ethanol. For the same reason it is also used as a component of the fuel mixture for carbureted compression ignition model engines.
Ether starting fluid is sold and used in countries with cold climates, as it can help with cold starting an engine at sub-zero temperatures.
Fuel ĭiethyl ether has a high cetane number of 85–96 and is used as a starting fluid, in combination with petroleum distillates for gasoline and diesel engines because of its high volatility and low flash point. It is particularly important as a solvent in the production of cellulose plastics such as cellulose acetate. Īnother reaction that can be used for the preparation of ethers is the Williamson ether synthesis, in which an alkoxide (produced by dissolving an alkali metal in the alcohol to be used) performs a nucleophilic substitution upon an alkyl halide. Getting a good yield of ether requires that ether be distilled out of the reaction mixture before it reverts to ethanol, taking advantage of Le Chatelier's principle. The reaction to make diethyl ether is reversible, so eventually an equilibrium between reactants and products is achieved. At higher temperatures, ethanol will dehydrate to form ethylene. This reaction must be carried out at temperatures lower than 150 ☌ in order to ensure that an elimination product ( ethylene) is not a product of the reaction. A hydrogen ion protonates the electronegative oxygen atom of the ethanol, giving the ethanol molecule a positive charge:ĬH 3CH 2OH + H 3O + → CH 3CH 2OH + 2 + H 2OĪ nucleophilic oxygen atom of unprotonated ethanol displaces a water molecule from the protonated ( electrophilic) ethanol molecule, reforming the hydronium ion and yielding diethyl ether.ĬH 3CH 2OH + 2 + CH 3CH 2OH → H 3O + + CH 3CH 2OCH 2CH 3 The acid dissociates in the aqueous environment producing hydronium ions, H 3O +. Ethanol is mixed with a strong acid, typically sulfuric acid, H 2SO 4. ĭiethyl ether can be prepared both in laboratories and on an industrial scale by the acid ether synthesis.
Vapor-phase dehydration of ethanol over some alumina catalysts can give diethyl ether yields of up to 95%. This process uses solid-supported phosphoric acid catalysts and can be adjusted to make more ether if the need arises. Most diethyl ether is produced as a byproduct of the vapor-phase hydration of ethylene to make ethanol. It has been used as a recreational drug to cause intoxication. It was formerly used as a general anesthetic, until non-flammable drugs were developed, such as halothane. It is commonly used as a solvent in laboratories and as a starting fluid for some engines. It is a colourless, highly volatile, sweet-smelling ("ethereal odour"), extremely flammable liquid. Diethyl ether, or simply ether, is an organic compound in the ether class with the formula (CH 3CH 2) 2O or (C 2H 5) 2O, sometimes abbreviated as Et 2O, where Et stands for monovalent ethyl group CH 3CH 2 which is often written as C 2H 5 (see pseudoelement symbol).
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