Thermal Program Desorption Mass Spectrometry of PAHs from Mineral and Organic Surfaces

Abstract

This research investigated the release of polycyclic aromatic hydrocarbons (PAHs) from spiked materials using thermal desorption mass spectrometry. Experimental methods were developed to obtain real-time PAH desorption data through use of a thermal program desorption probe. Data analysis techniques were investigated to explore the thermal desorption profiles of milligram-size samples. Peak temperatures of desorption were observed to vary among PAHs and among sorbents. For the same absorbent, peak temperatures increased with an increase of PAH molecular weights. For the same PAH, peak temperatures increased as the sorbent varied from sand to alumina to XAD-4 to kaolin. These results have been interpreted in terms of a combined model that include both an activation energy and a desorption/volatilization rate coefficient.