Supercritical Fluid Extraction

Supercritical fluid extraction is an extraction technique that uses pressure and temperature to effect recovery of organic compounds from solid, semi-solid samples. The use of supercritical fluids in the laboratory was initially focused on their use in chromatography, particularly capillary column supercritical fluid chromatography (SFC), and most recently as packed column SFC. The properties of a supercritical fluid allow selective extraction of organic compounds from sample matrices. This chapter presents the principles and instrumentation for supercritical fluid extraction. It helps the students to interpret a phase diagram for a supercritical fluid. The chapter also helps the students to identify and select appropriate operating conditions for supercritical fluid extraction. It is important that the extraction vessel is full to its capacity as this allows maximum solvent–matrix–compound interaction.