Over the past decade there has been a substantial interest in supercritical fluids (SCFs) from both the academic and industrial communities. An SCF is a fluid above its critical temperature and pressure. Three factors have contributed to the recent attention given to SCFs: (1) the environmental problems associated with common industrial solvents (mostly chlorinated hydrocarbons), (2) the increasing cost of energy-intensive separation techniques (for example distillation), and (3) the inability of traditional techniques to provide the necessary separations needed for emerging new industries (microelectronics, biotechnology, etc.). The availability of inexpensive, nontoxic SCF solvents such as CO2 and their attractive properties has renewed interest in SCF extraction as a viable commercial separation technique. SCF extraction has been applied to a wide variety of areas, including most recently various aspects of environmental control.