Licorice is a plant widely used for medicine, in the making of cigarettes, in insecticides, in candy making and in food flavorings. Typically, the root is the basis for the preparations, and it is manipulated by many chemical and manual procedures to produce the desired end product. The essential oil in licorice, like other plants' essential oils, is not easily removed from the plant using home equipment because it involves distillation and extraction chemicals and equipment found in laboratories. Referring to Nelida E. Gomez of the Smithsonian Tropical Institute and what she calls "a simple method to extract essential oils," you may find it rather complex. You can compromise and make an extract of the licorice plant that will contain some of the essential oil.
Clean the licorice root by scrubbing it under running water to remove any soil or plant debris. You can use a soft brush to get into the crevices. If you bought the root dried, it has probably already been well washed and there is no need to clean it further. You should cut apart a large mass of roots into small pieces so that you can clean it properly.
Soak the dried root (if necessary) overnight in water to plump it up. Fresh roots will retain their moisture content for many days and should not require an additional soaking.
Place the root into a food processor or blender with equal parts of water and pulse it until the chopped pieces are the size of sawdust.
Pour the mixture of water and roots into a pot and place over low heat. Cover the pot and allow it to simmer for about an hour to release the essential oils. You want to keep the pot covered to keep the volatile compounds from escaping in the steam.
Remove the pot from the heat and allow to cool without removing the pot cover. Once it has reached room temperature, strain the liquid and pour into a light-proof container, cover and refrigerate.