Objective To establish a method for simultaneous determination of 12 individual volatile organic compounds in workplace air by gas chromatography.
Methods The target compounds were adsorbed by activated carbon tube and desorbed by carbon disulfide. On the basis of programmed temperature single-program chromatographic separation, this study additionally adopted programed flow separation method by using DB-FFAP capillary column to improve chromatographic separation efficiency. Then, the individual compounds were measured with flame ionization detector.
Results The sampling efficiencies of 12 volatile organic compounds including methyl cyclohexane, ethyl acetate, butanone, benzene, ethyl acrylate, methyl isobutyl ketone, toluene, ethylbenzene, para-xylene, ortho-xylene, styrene, and cyclohexanone in the workplace air simultaneously collected by activated carbon tubes were between 95.3% and 99.4%. The samples could be stored in the refrigerator at 4℃ for 5 days. The precisions ranged from 0.30%-0.93%. The correlation coefficients were greater than 0.999 provided the target chemicals were in the range from 7 μg/mL to 500 μg/mL, with the detection limits of 0.012-0.058 μg/mL, desorption efficiencies of 95.8%-103.3%, and accuracies of 2.1%-4.6%.
Conclusion This method has a high accuracy and sensitivity. After changing from single program analysis to dual-program analysis, the analysis efficiency was increased by 57% due to the accelerated chromatographic separation, indicating that the method is applicable to simultaneous determination of 12 individual volatile organic compounds in the air of workplace.
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