Supercritical Fluid Extraction- Process Simulation and Design

Abstract

Supercritical fluid extraction (SFE) currently finds application in the food and petroleum industries. Research is aimed at using the unique properties of supercritical fluids to perform industrially significant separations. One major problem in application of SFE to separations is the lack of simulation/design experience for these processes. The work of the Separations Research Program at the University of Texas involves both the development of fundamental models and design procedures so that industry can better design separations processes. This paper will briefly discuss the previous experimental work done in the area of SFE, the experimental system and equipment currently being used at the University of Texas to study SFE and our first attempt to simulate this process using our own experimental data. In our case study, we will use data taken from one experimental run to simulate process flows, energy requirements and process conditions when separating isopropyl alcohol (IPA) from water employing supercritical carbon dioxide as the solvent. The SFE process is modeled using a commercially available computer process simulation program provided by Simulation Sciences, Inc. As might be expected, very little is known about the liquid-liquid and vapor-liquid equilibrium for multicomponent systems at high and supercritical pressures where there is a high degree of liquid phase non-ideality. Experimental data was used to specify separations where this data is currently unavailable. In addition, a standard data generation package was utilized from the process simulator to calculate this data where applicable conditions were met.