Question

How is diethyl ether prepared by continuous etherification process?

Answer 1

When an excess of ethyl alcohol is distilled with concentrated H₂SO₄ at 413 K (140 °C), diethyl ether is formed.
This reaction takes place in two steps:

Step-I: Formation of ethyl hydrogen sulphate:

When excess of ethyl alcohol is heated with concentrated H₂SO₄, ethyl hydrogen sulphate is obtained.

`C_2H_5-OH+H-O-SO_3H->C_2H_5_O-SO_3H+H_2O`

Ethyl alcohol   Conc.sulphuric acid           Ethyl hydrogen sulphate

Step-II: Formation of diethyl ether: Ethyl hydrogen sulphate then reacts with excess of ethyl alcohol at 413 K and forms diethyl ether.

`C_2H_5-O-SO_3H+OH-C_2H_5"413K"/"">C_2H_5-O-C_2H_5+H_2SO_4`

Ethyl hydrogen                   Ethyl                                 Diethyl ether
sulphate                            Alcohol