Thermal Extraction Outgassing

The difference between thermal extraction and the analytical pyrolysis systems described earlier lies in the consideration of the sample quantity and the applied temperatures. Even inhomogeneous materials, bulk materials or complete assemblies can be investigated at temperatures below pyrolysis, releasing [Pg.76]

In the field of environmental analysis, thermal extraction is proposed by an EPA method for the quantitative analysis of semi-volatile compounds from solid sample materials. The US EPA method 8275 is a thermal extraction capillary GC-MS procedure for the rapid and quantitative determination of targeted PCBs and PAHs (polynuclear aromatic hydrocarbons) in soils, sludges and solid wastes. This method requires extraction temperatures of 340 C for 3 min for the quantitative desorption of the PCBs (EPA, 1996). [Pg.79]

Another very flexible solution for numerous applications in pyrolysis, outgassing or thermal extraction experiments is the use of a micro-furnace, which can be resistively heated to temperatures above 1000 C (Roussis and Fedora, 1998). The sample is placed in a small, low, thermal mass cup of 50-80 pL volume, which is dropped into the heated pyrolysis furnace consisting of a vertical quartz tube. The furnace tube size is comparable to a GC inlet liner with 4.5 mm inner diameter and 12 mm length and allows programmable temperature profiles with heating rates of up to 200 C/min (Frontier Laboratories Ltd., Japan). [Pg.75]

Special focus has been set to the widely used and popular sample preparation methods as there are the pressurized liquid extraction (RLE), the thermal extraction of materials and food (outgassing), and in detail on the QuEChERS pesticide sample preparation used for GC-MS and LC-MS. As a consequence of the higher matrix load of these extracts and the recommended GC injection techniques, concurrent backflush, preventive maintenance and inlet deactivation became current topics of discussion. Olfactometry solutions have been added for apphcations in flavour analysis. [Pg.882]

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