York-FGAM Dual channel GC-FID
Contact: Dr Jim Hopkins
The York-FGAM dual channel gas chromatograph can be used for either in-situ or off-line sampling of a range of volatile organic compounds (VOCs) including C2 – C9 non methane hydrocarbons (NMHC), C2 – C6 oxygenated volatile organic compounds (OVOC), selected monoterpenes and dimethyl sulphide (DMS).
The system briefly comprises a multi-bed charcoal-based adsorbent trap for pre-concentration of the analytes before injecting them into the GC oven. The mixture is then split in an approximate 50:50 ratio between two GC columns, a porous layer open tubular (PLOT) column for separation of NMHCs and a LOWOX column for separation of OVOCs and monoterpenes. Two flame ionisation detectors (FID) are used for detection of analytes. A more detailed description can be found in Hopkins et al. 2003.
Two almost identical instruments exist and have been deployed on many different field campaigns over the last five years or more. The instrument took part in the ACCENT OVOC intercomparison experiment at the SAPHIR chamber in Julich, Germany, where it performed extremely well and was able to accurately quantify twelve of the fourteen target OVOCs (not able to quantify formaldehyde or 2-methyl-3-buten-2-ol). A paper (Apel et al. 2008) detailing the experimental procedures and results has recently been submitted to JGR.
A two-column method for long-term monitoring of non-methane hydrocarbons (NMHCs) and oxygenated volatile organic compounds (o-VOCs). Hopkins J.R., Lewis A.C., Read K.A.. Journal of Environmental Monitoring, 2003, volume 5, issue 1
Intercomparison of oxygenated volatile organic compound (OVOC) Measurements at the SAPHIR atmosphere simulation chamber. E. Apel, T. Brauers, R. Koppmann, R. Tillmann, C. Holzke, R. Wegener, J. Bossmeyer, A. Brunner, T.M. Ruuskanen, M. Jocher, C. Spirig, R. Steinbrecher, R. Meier, D. Steigner, E. Gomez Alvarez, K. Muller, S. J. Solomon, G Shade, D. Young, P. Simmonds, J.R. Hopkins, A.C. Lewis, G. Legreid, A. Wisthaler, A. Hansel, R. Blake, K. Wyche, P.S. Monks. In submission to JGR.