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“ Crude extracts ” obtained from most natural sources cannot be used as is from a supercritical fluid (SCF) plant and have to be reprocessed to eliminate water, pigments and waxes so as to become “clean extracts” that are concentrated in active compounds for direct use as ingredients in food, cosmetics or nutraceuticals/pharmaceuticals. On the other hand, the solid or liquid raw material can be processed as the ingredient itself from which unwanted compounds are eliminated and/or in which a valuable solute is infused. Several on-line or off-line processes are proposed so as to obtain such “ready-for-use” ingredients by combination of supercritical fluid processes (extraction, fractionation, impregnation) and other techniques including vacuum and molecular distillation, centrifugation and dehydration, adsorption on specific adsorbents, cold filtration and winterisation.

Supercritical carbon dioxide (SF CO2) is widely used as a “green” solvent for extraction, fractionation, formulation, etc., in hundreds of industrial plants, mainly manufacturing products from natural vegetal raw materials as well as food ingredients, cosmetics and perfumes, nutraceuticals, and phytopharmaceuticals. In this brief introduction to supercritical fluid technology, after presentation of the main physicochemical properties of SF CO2, the principal applications in the agrofood industries are illustrated by typical examples to show the great potential of various processes to deliver high-quality products, possibly labeled organic, while participating in the move to environmentally friendly “sustainable” development.

Alkoxysilane having various functional headgroups (amino and mercapto) and morphologies was deposited by supercritical CO(2) onto a porous dielectric material to replace the metallic barrier used in semiconductor devices. These organic layers were successfully coated with Cu. The morphologies of the stacks were investigated by X-ray and neutron reflectometry and atomic force microscopy. Whereas PVD Cu deposition is not adapted to silanized dielectric material with mercapto and aminopropyltrimethoxysilane but acceptable with aminoethylaminopropyltrimethoxysilane, the MOCVD process is more interesting. XRR and NR data clearly indicate that silane layers remain intact after copper deposition and, depending on the Cu immobilization capability of the chemical function of the silane and its orientation into the layer, the Cu film morphologies are different. Dense, thin films having small Cu grains were obtained with an aminoethylaminopropyltrimethoxysilane layer, and thick films having a low density and large Cu grains were obtained with an aminopropyltrimethoxysilane layer. Nucleation and growth mechanisms are discussed.