Thermal Desorption-Gas Chromatography or Gas Chromatography-Mass Spectrometry for Analysis of Semi-Volatile Compounds on Atmospheric Particulate Matters

A thermal desorption (TD) device was developed and coupled to gas chromatograph (GC) or gas chromatograph-mass spectrometer (GC-MS) for the qualitative and quantitative analysis of semi-volatile organic compounds on atmospheric particulate matters (PM). The TD was operated by direct heating and placed on the top of GC injector, leading to high heating rate and easy transfer of analytes to GC without re-focusing of analytes by cold trap. The materials used for supporting PM samples, desorption temperature and time, and types of sample injection were investigated for the detection of sixteen polycyclic aromatic hydrocarbons (PAHs) and nine n-alkanes. The limits of detection of the proposed TD-GC method were in the range of 0.014–0.094 ng for PAHs, and 0.016–0.026 ng for n-alkanes, with coefficients of correlation above 0.9975. The TD-GC method was applied to the determination of trace PAHs and n-alkanes on PM10 samples from three cities. The recoveries were in the range of 95%–135% (PAHs) and 95%–115% (n-alkanes). Finally, the TD was coupled to GC-MS for comparison of the contents of PAHs and n-alkanes on PMx with different particulate size (x = 10, 5, 2, 1, 0.5, 0.25, 0.1).

A thermal desorption (TD) device was developed and coupled to gas chromatograph (GC) or gas chromatograph-mass spectrometer (GC-MS) for the qualitative and quantitative analysis of semi-volatile organic compounds on atmospheric particulate matters (PM). Then, the contents of polycyclic aromatic hydrocarbons and alkanes on PMx with different particulate size from three Chinese cities were compared in detail.Figure optionsDownload as PowerPoint slide