1-mL Reservoir Solvent Introduction Orifice Threaded
Viton O-ring 4-mL Reservoir Solvent Introduction Orifice Threaded
4.5 cm
Figure 6. Teflon block apparatus for extraction of organic compounds from particulates collected on small dichotomous filter elements. The filter element is sealed in the block cavity in contact with the solvent reservoirs, and extraction is conducted by ultrasonic agitation. The solvent extract is then removed and concentrated by a factor of 100 or more prior to GC/MS analyses
grammed GC analysis can then be initiated. Uniformly heated transfer lines are critical features of the desorption apparatus. Cold spots will cause condensation of the less volatile compounds, resulting in incomplete transfer and loss of GC resolution. For the analysis of trihalomethanes in water, a purge and trap method followed by thermal desorption has proved to give reliable quantitation (15). The method can be used successfully for quantitation of compounds that are
