Determination of CH4, CO2 and N2O in air samples and soil atmosphere by gas chromatography mass spectrometry, GC-MS.
A method for determination of the climate gases CH4, CO2 and N2O in air samples and soil atmosphere was developed using GC-MS. The method uses straightforward gas chromatography (separation of the gases) with a mass spectrometric detector in single ion mode (specific determination). The gases were determined with high sensitivity and high sample throughput (18 samples h(-1)). The LOD (3sigma) for the gases were 0.10 micro L L(-1) for CH4, 20 microL L(-1) for CO2 and 0.02 microL L(-1) for N2O. The linear range (R2 = 0.999) was up to 500 microL L(-1) for CH4, 4000 microL L(-1) for CO2 and 80 microL L(-1) for N2O. The samples were collected in 10 mL vials and a 5 microL aliquot was injected on column. The method was tested against certified gas references, the analytical data gave an accuracy within +/-5% and a precision of +/-3%. The presence of < or = 10% by volume of C2H2 (often used experimentally to prevent N2 formation from N2O) did not interfere with detection for the targeted trace gases.
Ekeberg
Dag
D
Department of Chemistry, Biotechnology and Food science, P.O. Box 5003, Agricultural University of Norway, N-1432 As, Norway. Dag.Ekeberg@nlh.no
Ogner
Gunnar
G
Fongen
Monica
M
Joner
Erik J
EJ
Wickstrom
Torild
T
D000393:Air Pollutants / Q000032:analysis*; D002245:Carbon Dioxide / Q000032:analysis*; D008401:Gas Chromatography-Mass Spectrometry; D008697:Methane / Q000032:analysis*; D009609:Nitrous Oxide / Q000032:analysis*; D012680:Sensitivity and Specificity; D013048:Specimen Handling
D000393:Air Pollutants; D002245:Carbon Dioxide; D009609:Nitrous Oxide; D008697:Methane