Optimized Method for Determination 57 Volatile Organic Compounds in Nitrogen Using GC x GC-FID

The sample containing 57 volatile organic compounds (VOCs) in nitrogen at a nominal 1 ppmv was prepared in our lab using weighting method. A methodology for determination of the 57 VOCs using a two-dimensional gas chromatography equipped with Deans switches and two flame ionization detectors (GC x GC-FID) was developed and validated for resolution, asymmetry, sensitivity, precision (intra-day precision and inter-day precision), linearity, limit of detection (LOD), limit of quantification (LOQ) and accuracy. In this study, resolution, asymmetry and sensitivity of the analytical method were improved,intra-day precisions of all the compounds were <1% and inter-day precisions were between 0.9 and 3.0%. In addition, LOCI and LOD were in the range of 0.024-0.185 ppmv and 0.012-0.092 ppmv, respectively. An excellent linearity was obtained (R-2 > 0.9995). At the meantime, the accuracy of the analytical method was evaluated by determining the concentration of a certified reference material.