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[Determination of chloroform and carbon tetrachloride in residential air by capillary gas chromatography].

OBJECTIVE
To establish solvent desorption capillary gas chromatography method for determination of chloroform and carbon tetrachloride in residential air.


METHODS
The sample was absorbed by active carbon glass tube, then desorbed by Acetone and determined by Capillary Gas Chromatography.


RESULTS
Linear range of this method: 5.0 x 10(-4)-1.0 x 10(-1) mg/m3 for chloroform, 1.9 x 10(-4)-1.0 x 10(-2) mg/m3 for carbon tetrachloride. The sample could be stored in the active carbon glass tube for 7 days. The re-occurrence rate of this method is good. RSD is: 0.41%-1.54% for chloroform, 0.31%-1.03% for carbon tetrachloride. Detection limit of this method: 1.5 x 10(-3) ng for chloroform, and 5.8 x 10(-4) ng for carbon tetrachloride. Recovery rate for different concentrations: 88.5%-98.6% For chloroform, and 91.0%-99.0% for carbon tetrachloride. Sampling efficiency: 93.7%-99.2% for chloroform, and 90.6%-99.2% for carbon tetrachloride. Other Volatile halogenated hydrocarbons with similar structures and similar nature in the residential air do not interfere the measurement.


CONCLUSION
The method was easy and quick, with high sensibility. It was applicable to monitor the chloroform and carbon tetrachloride in residential air.