How do you separate oil and alcohol?

Answer 1

You have two basic options. I'm going to assume that whatever oil you're trying to separate from the alcohol is highly volatile (like fragrant essential oils from plant material). Both methods require a little bit of time.

• Evaporation - simply place the oil and alcohol mixture in a container and wait for the alcohol to evaporate. This process can be greatly hastened by putting the mixture in a large flat dish to increase the surface area. The alcohol will evaporate faster than the oil.
• Separation - mix equal parts alcohol/oil concentration and water. Then, place this mixture in a clear container and wait for the components to separate. Ethyl alcohol will dissolve into the water. Next, the denser water will sink to the bottom and the oil will float on top. Then you can skim or suck the oil off of the top of the water. If you have one, a separation funnel makes this really easy.

If you want the alcohol, what you can do is use an alembic (home-made or otherwise) to capture the naturally evaporating alcohol. Thin copper tubing works best. You can place a lid on a container with the alcohol/oil mixture and run that through a cooling medium (like another container filled with ice) and into another sealed container that sits lower than the one with your mixture.

Answer 2

Oil and alcohol can be separated by using a separation technique called fractional distillation. This method relies on the different boiling points of oil and alcohol. By heating the mixture and collecting the vapors at different temperatures, the components can be separated based on their boiling points.