Hier finden Sie wissenschaftliche Publikationen aus den Fraunhofer-Instituten.

A closer look at gas antisolvent crystallisation

: Weber, A.; Kümmel, R.; Kraska, T.

International Society for the Advancement of Supercritical Fluids:
Particules design, materials and natural products processing. Proceedings of the 7th meeting on supercritical fluids. Tome 1 : Particle design, materials and reactions
Vandoeuvre: Institut National Polytechnique de Lorraine, 2000
ISBN: 2-905267-31-0
Meeting on Supercritical Fluids <7, 2000, Antibes>
Fraunhofer UMSICHT Oberhausen ()
Kristallisation; Phasengleichgewicht; Thermodynamik; Gasantisolvent; PCA Prozess; crystallization; gas antisolvent; phase equilibria; thermodynamics; PCA process

The special properties of compressed fluids give access to novel crystallisation processes with distinctive advantages over conventional methods. By precipitation with compressed antisolvents (PCA), it is possible to control the characteristics of the solid products to a high degree. In recent years several physical models have been developed on the process but there remains still a lack of understanding. In order to control complex procedures as coprecipitation or selective crystallisation further investigations are necessary. A promising tool to investigate technical multicomponent processes is the discussion in phase diagrams. A process can be traced by a path in a phase diagram. The combination of different kinds of phase diagrams such as px-, Tx-sections, pT-projections and global phase diagrams provide a qualitative and quantitative insight in a process. In case of PCA solid-fluid equilibria are necessary for the understanding of the characteristics of the product. Furthermore, metastable fluid-fluid equilibria are important because the PCA process corresponds to jump into a non-stable region of the phase diagram.