Preparation of Ethanol

(1) Ethanol can be prepared by the hydrolysis of ethane.

C₂H_4(g) + H₂SO_4(aq)  →  C₂H₅HSO_4(aq)

C₂H₆HSO_4(aq) + H₂O_(L)  →  C₂H₆OH_(aq) + H₂SO_4(aq)

(2) Preparation from fermentation of starch –

2(C₆H₁₀O₆)_n(s) + nH₂O_(L)  →  nC₁₂H₂₂O_11(aq)

C₁₂H₂₂O_11(aq) + H2O(L)  →   2C₆H₁₂O_6(aq)

C₆H₁₂O_6(aq) →  2C₂H₆OH_(aq) + 2CO_2(g)

The ethanol obtained here is purified through distillation.