High water content, physical sample size, and low concentration of analytes can hinder thermal desorption analysis of volatile compounds of interest such as fragrances, off-odors and reaction products. The GERSTEL Thermal Extractor (TE) eliminates this problem by concentrating the analytes on a standard TD adsorbent tube while eliminating water and leaving the matrix behind. In the sample preparation stage, a solid, gelatinous or liquid sample is placed in the TE tube which is then heated to the desired temperature (typically 30°C to 100°C) while an adjustable flow of inert gas is passed through the TE tube. The inert gas flowing around the hot sample extracts the water and the volatile components, which are then trapped on the Tenax bed of the TD tube. The water is eliminated by "dry purging" the Tenax tube. The tube is then removed and placed in a thermal desorption system. The Tenax tube is analyzed using the GERSTEL thermal desorption technique of refocusing compounds in the Cooled Injection System CIS, and then introducing them as a narrow band onto the GC column for separation. The TE can also be used for bulky samples, due to its much larger tube size (14 mm ID).
Main Features and Advantages