Industrial application of Fractional distillation

On a large scale, fractional distillation is used:

(i)In fractional distillation of crude oil in an oil refinery.

Crude oil is a mixture of many fractions.

When heated in a furnace, the different fractions separate out according to their boiling point.

Very heavy bitumen does not boil.

 It collects at the bottom

 In Kenya, fractional distillation takes place at Changamwe in Mombasa.

(ii)In fractional distillation of air.

Air contain a mixture of three main useful gases which are condensed by cooling to very low temperature

 (-200oC) to form a liquid.

The liquid is then heated.

Nitrogen is the most volatile(-196 oC) and thus comes out as the first fraction.

Argon (at -186 oC) is the second fraction.

Oxygen ( at -183 oC) is the last fraction.

The three gases are very useful industrial gases.