Application of supercritical fluids replaces organic solvents

Organic solvents are used widely to extract biological agents. A project funded by the BMBF and coordinated by the Fraunhofer Institute for Environmental, Safety, and Energy Technology (UMSICHT) sets out to explore the possible use of supercritical fluids instead. The best-known practical example of the extraction of biological agents using supercritical liquids is probably the extraction of caffeine from unroasted coffee beans. While this process is well-established, supercritical carbon dioxide could be an environmentally friendly alternative for many other extraction processes. However, a better understanding of the physical and chemical processes involved needs to be developed before this is possible. The specific goal of this project is research on the extraction of biological agents from plant matrices, specifically from red clover, sage and rapeseed, and the treatment of heterogenic matrices like wood or paper, which is possible with hydrophobic substances by means of supercritical carbon dioxide. During the course of the extraction and treatment experiments, researchers will explore the impact of a wide variety of parameters on the matrix and the products. These include the impact of varying matrix properties, process/operation modes, pressure, temperature and mass/volume flow rates of the supercritical fluid. The results will find later industrial applications in cosmetics, food production and construction as well as in sectors like the chemical, pharmaceutical and textile industries