Pure and Applied Chemistry

Solubilities in supercritical fluids are of great importance in a wide variety of applications. These applications include: production of controlled drug delivery systems, powder processing, pollution prevention and remediation, methods for spraying paints and coatings, precipitation/crystallization processes, bioseparations, and food processing. Examples of some of these applications will be given.

Supercritical fluid processes make use of the significant variation of solubility with pressure when the solvent is a supercritical fluid. This permits the accomplishment of many processes that would be otherwise very difficult to achieve. To fully understand the benefits of such processes, one must understand the phase behavior of such systems. The types of phase behavior that can be observed will be discussed, along with the ways that this behavior can be used to modify solubilities in such fluids.

There have been many methods proposed for the experimental determination of solubilities in supercritical fluids. These will be reviewed in general, and recommendations for preferred methods given.

Solubilities in supercritical fluids can be correlated and predicted by making use of thermodynamic calculations involving equations of state, as well as by other methods. The various methods will be reviewed, and recommendations given for various applications.