Fractional Distillation of Crude Oil When crude oil reaches the refinery, it is heated un�l it evaporates. As the vapour (hydrocarbon gases) condense back into liquids, the column sorts the different frac�ons from each other and removes them from the sides of the column.

The larger hydrocarbons, with the high boiling points, turn back into liquids at the base of the column and the smaller hydrocarbons stay as gases. They rise up the column and condense at different levels. At the top of the column there are a number of hydrocarbons with low boiling points (between 20ºC and 70ºC) - these remain as gases.

Small Molecules: Low boiling point Very volatile Easier to ignite Flows easily

Large Molecules: High boiling point Not very volatile Harder to ignite Does not flow easily

Crude Oil

Bottled Gas

Petrol(Gasoline)

Chemicals

Jet fuel,Paraffin forlighting and

heating

Diesel fuels

LubricatingOils, Waxes and Polishes

Fuel for Ships, Factories

and CentralHeating

Bitumen forRoads and

Roofing

Refinery Gas < 40°C

Petrol 40°C - 205°C

Residue> 600°C

Naphtha60°C - 100°C

Kerosine175°C - 325°C

Diesel250°C - 350°C

Lubricating Oil300°C - 370°C

Fuel Oil370°C - 600°C

Fractionating column

trucktruck

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