Compounds in Source Emission by Canister Sampling-Preconcentration/Gas Chromatography-Mass Spectrometry

KeyWord:volatile organic compounds  preconcentration  gas chromatography-mass spectrometry  source emission  summa canister

Abstract:

      An analytical method was established for the determination of 118 volatile organic compounds(VOCs) in source emission by preconcentration/gas chromatography-mass spectrometry with FID detector,in combination with Deans Switch and cold oven technique.Samples were collected with a summa canister,and diluted before analysis.C2-C3 compounds were determined with FID,and quantified by external standard method.The remaining compounds were determined by mass spectrometry(MS),and quantified by internal standard method.Results showed that the calibration curves for 118 VOCs exhibited good linearity in the concentration range of 0.5-30 nmol/mol,with the correlation coefficients(r2) of 0.995 3-0.999 9.The limits of detection and the limits of quantification were in the ranges of 0.01-0.38 ¦Ìg¡¤m-3 and 0.03-1.51 ¦Ìg¡¤m-3£¬respectively.The average recoveries at low,medium and high spiked levels ranged from 76.4%to 110%with the relative standard deviations(RSDs,n=7) of 0.30%-6.0%.The method was applied to the determination of VOCs in the exhaust gases of mobile source(forklift) and stationary sources(shoe factory,furniture factory,printery,plastic factory and shipyard).Different degrees of VOCs pollution were detected,in which concentrations of total VOCs(TVOC) in exhaust gases from the forklift and stationary sources were 33.50-35.25 mg¡¤m-3 and 44.54-211.71 mg¡¤m-3,respectively.The method was simple,rapid,stable,sensitive and accurate£¬and was suitable for the determination of VOCs in mobile and stationary source emissions.