Submitted to: Annual Meeting and Expo of the American Oil Chemists' Society
Publication Type: Abstract Only
Publication Acceptance Date: February 26, 2004
Publication Date: May 12, 2004
Citation: TAYLOR, S.L., ELLER, F.J. HEXANE REMOVAL FROM OIL MIXTURES USING LIQUID CO2 AND ANALYZED VIA SFC. ANNUAL MEETING AND EXPO OF THE AMERICAN OIL CHEMISTS' SOCIETY. 2004. Technical Abstract: Liquid carbon dioxide (L-CO2) was used to remove hexane from hexane/soybean oil (SBO) mixtures. A fractionation column was constructed that included a precooling section and four separate zones and had a total height of 253.2 cm. It was packed with a protruded stainless-steel packing which provided a 94% void volume. A hexane/SBO mixture was introduced into the column above the first zone by a liquid metering pump. L-CO2, at 25°C and 1350 psi, was pumped through the hexane/SBO mixture at a flow rate of 3-4 L/min (expanded gas). After passing through the hexane/SBO mixture, the CO2 stream was directed through the injector of a supercritical fluid chromatograph (SFC). At timed intervals, the SFC program was initiated and a sample was injected onto a capillary column and analyzed with a flame ionization detector. Relative peak areas of the hexane and SBO were compared to determine the residual hexane levels. The extractions proceeded for set volumes of L-CO2 to determine the amount required to effectively remove hexane from the mixtures. The SFC program was optimized to analyze the hexane portion of the sample. This technique provided real time on-line monitoring of the extraction process. The SFC data were compared to the residual hexane that remained in the extracted SBO. ISO Method 9832:2002 was used to determine the residual hexane levels.