The extraction of compounds from these natural products is an example of solid/ liquid extraction-the solid being the natural product and the liquid being the solvent into which the compounds are extracted. In research, a Soxhlet extractor is often used for solid/liquid extraction.
Although solid/liquid extraction is the most common technique for brewing beverages and isolating compounds from natural products, liquid/liquid extraction is a very common method used in the organic laboratory, specifically when isolating reaction products. Reactions are typically homogeneous liquid mixtures and can therefore be extracted with either an organic or aqueous solvent. Organic reactions often yield a number of by products-some inorganic and some organic. Also, because some organic reactions do not go to 100% completion, a small amount of starting material is present at the end of the reaction. When a reaction is complete, it is necessary to do a workup, that is, separate and purify the desired product from the mixture of byproducts and residual starting material. Liquid/liquid extraction is a common separation step in this workup, which is then followed by purification of the product. There are two types of liquid/liquid extractions: neutral and acid/base. ...Show more