Fractional distillation
05/28/17
“How can we have distillation for materials with more than two substances?”
Distillation is the process of separating two substances using the science of evaporation and condensation in regard to different boiling points. However, how can we make this process happen for materials such as crude oil which are composed of many different substances? Well, let’s use our engineering mindset to find out. Let’s start out with a simple test tube. In this test tube, let’s also have another smaller tube at the midsection leading to a stationary beaker. Now let have the bottom portion of the main tube be immersed in a hot fluid. When we dispose a material into the tube, the hot fluid will heat the material until one of the substances evaporates. The gas from the evaporated substance will rise and move through the tube, eventually reaching the midsection tube, cooling and condensing into a liquid form in the beaker. Once all of this substance has been removed, we can swap out the old stationary beaker for a new one, replace the hot liquid with a bunsen burner, and repeat the process. This procedure is known as fractional distillation and is commonly employed for separating substances with numerous hydrocarbons.
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