Manufacture of Submicron Particles via Expansion of Supercritical Fluids

The RESS (rapid expansion of supercritical solutions) process offers interesting possibilities for producing submicron solid particles for high-value materials used, in particular, in the food and pharmaceutical industries. Despite extensive models and experimental data on the use of supercritical fluids in extraction processes, there are still uncertainties about the fundamental processes that contribute to particle formation in the RESS process. In the present research, the effect of the nozzle diameter and preexpansion conditions on particle size and morphology of a model system of carbon dioxide/cholesterol has been examined.