A Polyarc reactor was used to convert organic molecules to methane at the exit of the GC column equipped with an FID and split/splitless inlet. Methanol was used as the solvent and internal standard for these measurements. The mean deviation between the response factors and unity was 1.8%. The reactor was tested with different pesticide concentrations to determine the linearity of response and limits of detection. The measured concentrations and actual concentrations of the pesticides demonstrate linearity and accuracy of the detector response over three orders of magnitude. Based on the smallest possible peak area distinguishable from noise and the largest solvent peak area measured in this study, the Polyarc reactor gives a linear detector response over eight orders of magnitude in concentration. The response provided by the reactor is proportional to the number of carbon atoms in each molecule, despite the large differences in their chemical formulas and functionalities. The N, O, S, P and Cl atoms present in the pesticides have no effect on the response of the FID per carbon atom, because the molecules are completely converted to CH4 in the reactor. The reactor system is able to detect and remedy holdup or other GC issues that cause inaccuracies.
|Original language||English (US)|
|Specialist publication||American Laboratory|
|State||Published - Jan 1 2016|