Determination of Chlorofluorocarbons in Groundwater by Purge and Trap and Secondary Cold Trap Coupled with Gas Chromatography/Mass Spectrometry

Abstract

Abstract A method was established to determine the chlorofluorocarbons (CFCs) in groundwater by purge and trap and secondary cold trap coupled with gas chromatography/mass spectrometry (GC-MS). The groundwater samples were processed with absorption/thermal desorption/cold trap/thermal desorption, and GC-MS was used for quantitative and confirmatory analysis. The results showed that the relative standard deviations of chlorotrifluoromethane (CFC-11), dichlorodifluoromethane (CFC-12) and 1,1,2-trichlorotrifluoromethane (CFC-113) were 1.1%, 0.9% and 1.5%. The method linearity range of the CFC-11, CFC-12 and CFC-113 were 0.09 × 10−12−3.0 × 10−12 M, 0.04 × 10−12−3.0 × 10−12 M and 4.0 × 10−17−4.0 × 10−14 M, respectively. The correlation coefficients were greater than 0.99. The detection limit of CFC-11, CFC-12, CFC-113 were 4.4 × 10−14 M, 1.6 × 10−14 M and 5.36 × 10−18 M, respectively. The average recovery of the spiked samples was 95.4%−102.0%. The method was quick, sensitive, easy and feasible for the detection of CFCs in groundwater. According to the analysis results, the apparent age of groundwater can be calculated.