Analysis of volatile organic compounds in air using retention indices together with a simple thermal desorption and cold trap method

• Published in: Journal of Chromatography A Vol. 787; no. 1; pp. 205 - 214
• Main Authors: Kivi-Etelätalo, Eeva, Kostiainen, Olli, Kokko, Mariitta
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 07.11.1997; Elsevier
• Subjects: Air analysis; Analysis methods; Analytical chemistry; Applied sciences; Atmospheric pollution; Chemistry; Chromatographic methods and physical methods associated with chromatography; Environmental analysis; Exact sciences and technology; Gas chromatographic methods; Pollution; Retention indices; Thermal desorption; Trapping; Volatile organic compounds; Volatile organic compounds; Air analysis; Trapping; Thermal desorption; Retention indices; Environmental analysis; Electron capture detector; Chemical analysis; Hydrocarbon; Organic perhalocompound; Chromatographic retention; Benzene derivatives; Thermodesorption; Instrumentation; Volatile organic compound; Flame ionization detector; Halocarbon; Urban atmosphere; Gas chromatography; Retention index; N,N-Dimethylformamide; Carboxamide; Air pollution; Qualitative analysis; Nitrogen phosphorus detector; Detection; Quantitative analysis
• ISSN: 0021-9673
• DOI: 10.1016/S0021-9673(97)00663-8

A simple, low-cost thermal desorption and cold trap device was constructed and tested with a two-channel gas chromatograph equipped with SE-54 fused-silica capillary columns or a Al 2O 3/KCl column and flame ionization, nitrogenphosphorus or electron-capture detectors. Good repeatability was obtained in the identification of ten aromatic compounds, with use of n-alkanes as index compounds for the determination of retention indices. The performance of the equipment and method with real samples was evaluated for the determination of volatile halogenated compounds and small alcohols in urban air, and for the determination of N,N-dimethylformamide (DMF) in air nearby a chemical plant. A collection method was developed for highly volatile halogenated hydrocarbons and small polar alcohols. At ambient temperature they were not easily trapped completely and humidity was a problem. Drying tubes were beeded in front of the sampling tubes, which were placed inside copper tubes refrigerated in a cold box. Compounds were reliably identified, and some of the halogenated compounds and DMF were determined quantitatively.