SEPARATING MIXTURES [Continuing...]
Fortunately, however, distillation does not end there. We can also separate multiple liquids with boiling points and melting points very close to each other in a process known as fractional distillation. In fact, this process is used by many industries, especially the oil industries. Crude oil is a good example of a substance that undergoes fractional distillation in order to be useful to the average consumer; that's where we get our gas/fuel to run vehicles, ships and airplanes.
The Process:
Liquids with high boiling points have large, heavy particles, whereas those with low boiling points have small, light particles. The heavier particles need more energy to help them escape. Therefore, as before, the liquids with low boiling points evaporate and condense first and thus are separated from the rest of the mixtures.
But there is an important element that distinguishes fractional distillation from regular distillation. Fractional distillation uses a distillation column (or a fractionating column) to condense the liquids. Furthermore, the process' temperature is closely regulated in order to be obtain the purest form of the wanted liquid and thus be as accurate as possible.
The next page illustrates this process in a diagram.