Fundamentals of Supercritical Fluid Technology

S. PEREDA; S.B. BOTTINI; E.A. BRIGNOLE

Supercritical Fluid Extraction of Nutraceuticals and Bioactive Compounds

CRC Press

Año: 2007; p. 1 - 23

Solvents are used in large amounts in the chemical, pharmaceutical industry and in the recovery of natural products. In the search of environmentally friendly solvents, increasing attention is being paid to supercritical fluids (SCFs) for a wide variety of applications. For instance supercritical solvents are used in extractions, material processing, micronization, chemical reactions, cleaning and drying, among others. Supercritical and near critical fluids add a new dimension to conventional (liquid) solvents: their density dependent solvent power. The density of supercritical fluids can be easily tuned to the process needs, with changes in temperature, pressure and/or composition. Other important properties of supercritical fluids are their very low surface tension, low viscosity and moderately high diffusion coefficients. The design of processes using supercritical solvents is strongly dependent of the phase equilibrium scenario required in each case. The phase behavior in supercritical processes is highly sensitive to changes in operating conditions. Therefore phase equilibrium engineering plays a key role in the synthesis and design of these processes applications.