title: Automated gas chromatography with cryogenic/sorbent trap for the measurement of volatile organic compounds in the atmosphere.
abstract: An automated gas chromatographic system was constructed to easily adapt either the cryogenic trap or chemical sorbent trap for preconcentrating ambient levels of volatile organic compounds. Remarkable similarity in chromatograms from C3 to C10 was found between these two enrichment methods, except that the sorbent trap did not quantitatively trap the C2-hydrocarbons. In contrast to cryogenic trapping, the chromatographic conditions for more volatile compounds were substantially improved using the sorbent trap. Water interference on the porous-layer open tubular column was also better managed using the sorbent trap for the continuous analysis of humid room air. The similarity in peak profiles between the GC-flame ionization detection (FID) and a commercial GC-MS system, regardless of concentration levels, facilitated compound identification on the FID chromatograms based on a field mission involving analysis of 106 air samples.
authors.affiliation: Department of Chemistry, National Central University, Chungli, Taiwan.
authors.forename: J L
authors.initials: JL
authors.lastname: Wang
authors.forename: S W
authors.initials: SW
authors.lastname: Chen
authors.forename: C
authors.initials: C
authors.lastname: Chew
mesh_terms: D000327:Adsorption; D000393:Air Pollutants / Q000032:analysis*; D001322:Autoanalysis; D002245:Carbon Dioxide / Q000032:analysis; D002251:Carbon Tetrachloride / Q000032:analysis; D002849:Chromatography, Gas / Q000379:methods*; D008401:Gas Chromatography-Mass Spectrometry; D006813:Humidity; D014835:Volatilization
chemical_list: D000393:Air Pollutants; D002245:Carbon Dioxide; D002251:Carbon Tetrachloride