Simultaneous Determination of Volatile Chlorinated Hydrocarbons by Dual Detection using a Semi-Wide Bore Capillary Column.

Abstract

Headspace analysis was employed for the simple and rapid simultaneous gas chromatographic determination of volatile chlorinated hydrocarbons (VCH) in drinking water by dual detection using a semi-wide bore capiliary column (0.32 mm i.d.). For dual detection, an electron capture detector (ECD) and a flame ionization detector (FID), were employed in combination to attain the simultaneous determination at a low parts-perbillion level of 15 kinds of VCH with a single injection. After the equilibration time of 1 h, when 0.5 ml of headspace gas was injected into the gas chromatograph with a splitless injection (0.5 min), the capillary column permitted satisfactory separations for all target compounds without interference by trihalomethane. The sensitivity of detecting cis- and trans-1, 2-dichloroethylene using the FID was about 3-6 fold higher than that using the ECD with the detection limits of 1.0 and 0.7 ppb, respectively. The detection limits of the other VCH were 0.005 (carbon tetrachloride and 1, 1, 1-trichloroethane)-0.7 ppb (1, 2-dichloroethane) using the ECD, which shows a high sensitivity. The coefficients of variation were 3.2-8.8% with good precision and reproducibility.