Process of fractional distillation and property of the substances is use to separate

The main fractions include refinery gases, petrol, naphtha, kerosene, diesel oil, fuel oil, and a residue that contains bitumen.

The fractional distillation separate the products contain in crude oil using their different boiling temperatures. Each product is leaving the crude oil distillation column at different level with the lightest product at the top and the heaviest product at the bottom.