Thermal-desorption gas chromatographic procedure for screening coal fly ash for volatile organic compounds

Thermal desorption of coal fly ash in a flowing stream of helium liberates volatile compounds which are collected on Tenax resin. A chemical “fingerprint” of these components collected from the fly ash is obtained by using thermal desorption of the material collected on the Tenax resin and capillary-column gas chromatography. Compounds ranging in volatility from that of benzene (b.p. 80°C) through C₁-phenanthrene (b.p. ca. 360°C) are detected, but recoveries of components only through naphthalene (b.p. 218°C) are suitable for quantitative work. The method provides chemical information on volatile organic compounds complementary to that achieved by procedures based on solvent extraction.