Measurement of Hydrofluorocarbons, Perfluorocarbons and Chlorofluorocarbons in Ambient Air by Gas Chromatography and Mass Spectrometry

Poster Presentation

Prepared by R. Bramston-Cook, E. Bramston-Cook
Lotus Consulting, 5781 Campo Walk, Long Beach, CA, 90803, United States


Contact Information: randy@lotusinstruments.com; 310-569-0128


ABSTRACT

This paper reports on a method for the measurement of trace hydrofluorocarbons, perfluorocarbons and chlorofluorocarbon in ambient air. Details are provided for the hardware requirements and performance accomplished with a high performance gas chromatograph and mass spectrometer. To achieve measureable concentration levels, a cryotrapping system is required. However, ambient levels of water can interfere with the trapping process. Options are presented on how to eliminate moisture during the measurement sequence. And special operations are needed to fully recoverable the very volatile species, especially tetrafluoromethane (Freon 14). Included in the discussion are chromatographic conditions, sampling processes, especially for real time sampling, and data calculations. Results are provided for linearity and detection limit studies into the low pmol/mol (pptV) levels.