ABSTRACT
This chapter discusses unique functions of the supercritical fluid solvent. It explores the potential of supercritical fluid technology for creating industries of the future. Whether a fluid is in a gaseous phase or liquid phase depends on the balance of kinetic energy of its molecules and the energy of the intermolecular forces. Fluid properties including viscosity, diffusivity, thermal conductivity, dielectric constant, ionic product, are determined by the molecular interactions, and thus directly related to the distance of molecules in a fluid, namely the fluid density. The controllability of the phase behavior and the phase equilibrium are key features of supercritical fluid separation, extraction and reaction processes. One of the major applications of supercritical fluids is for extraction solvents. Because the liquid-like density, supercritical fluids show solubility for the non-volatile substances to some extent. Phase behavior undergoes great changes in mixed systems involving a supercritical fluid and the characteristics can be used in crystallization.
