Solvent extraction

• Solvent extraction involves using a solvent to remove the desired organic product from other substances in the reaction mixture.
• The choice of solvent within solvent extraction depends on two major factors. Firstly, the solvent should be immiscible with the solvent containing the desired product. Also, the desired organic product should be much more soluble in the solvent added than in the reaction mixture.
• In the first stage of solvent extraction, the reaction mixture is added into a separating funnel with the chosen solvent. Next, the stopper is placed into the funnel neck, and it is gently shaken. The contents should be left to separate into two layers. Finally, remove the stopper and open the tap to allow both layers to drain into separate flasks.
• During solvent extraction, it is more efficient to use smaller portions of solvent (e.g. 4 x 25cm3 instead of 1 x 100cm3). This way more of the desired organic product is removed.
• Once the organic product has been extracted from the original reaction mixture, it is still mixed with the new solvent. In order to remove the solvent, simple or fractional distillation can be used.