INTEGRATED ANALYSIS OF SOLID SAMPLES BY ONLINE SUPERCRITICAL FLUID EXTRACTION GAS-CHROMATOGRAPHY

A system for direct coupling of supercritical fluid extraction with carbon dioxide and capillary gas chromatography (GC) has been developed. Use of a double-oven gas chromatograph allows precise thermostating of all parts used for th extraction and sample transfer process. The valve position and the temperature are controlled by the GC panel. The system allows extraction chambers with dimensions from the micro to the semi-preparative scale. The modifications necessary for changing the vessel size and operation mode have been minimized. For small sample sizes, the whole extract is transferred to the analytical column and cryofocused there. The handling of larger amounts of sample or the performance of equilibration studies can be effected by using a "time-split" injection mode. The performance of the system was evaluated by the analysis of soil, plant material and smoke particles trapped on Tenax. © 1990.