Submitted to: Pittsburgh Conference
Publication Type: Abstract Only
Publication Acceptance Date: March 1, 1998
Publication Date: N/A
Technical Abstract: Processing that utilizes supercritical fluids has shown considerable promise because of the environmental compatibility, variable solvent power and mass transport properties of these fluids. Instrumentation originally designed for analytical purposes that utilizes supercritical fluids can also be applied to optimize processing conditions, thereby avoiding the cost, labor and time involved with operating pilot plant or larger facilities. Analytical supercritical fluid instrumentation has been used to study transesterification reactions conducted in the presence of supercritical carbon dioxide (SC-CO2) and a lipase-based catalyst, Novozyme SP 435, to produce esters from dissolved vegetable oils and alcohols. An automated supercritical fluid extraction (ASFE) has also been incorporated to evaluate the activity of lipase catalysts in the presence of SC-CO2, reversing the normal use of ASFE equipment. Using this approach, three lipases were shown to have a broad based activity for transesterifying various lipid species. Similarly, a sample preparation accessory (SPA) unit has been modified to permit the evaluation of several different types of catalysts for the synthesis of methyl stearate with respect to conversion and rate of reaction. ASFEs have also been used to study and optimize the extraction and fractionation of naturally-derived products such as vernonia or cedarwood oil, and phospholipid concentrates from seed oils. In these cases, the effect of CO2 density over the pressure range of 2,000-10,000 psi and at temperatures from 40-100 deg C has been utilized.