CRYSTALLIZATION OF INORGANIC COMPOUNDS WITH COMPRESSED OR SUPERCRITICAL CARBON DIOXIDE

摘要

The production of high quality ceramics requires precursors with a high chemical homogeneity. In the field of crystallization with compressed fluids especially the PCA process (Precipitation with Compressed Antisolvents) is capable of meeting the demands. This process is based on the dispersion of a primary solution (solvent and dissolved solids) via a nozzle into a compressed antisolvent. Because of the high solubility of the compressed antisolvent in the primary solvent, high supersaturations are reached leading to small and nearly monodisperse solids. It is also possible to precipitate two or more components simultaneously. The resulting microcomposites show a high chemical homogeneity and a small particle size, which implies a good sinterability of the products.