Determination of benzene series in soil and sediment with combined thermal desorption gas chromatography

Systematical experiments have been conducted to determine BTEX in soil and sediment using internal standard through combining thermal desorption and gas chromatography.This method has been proved simple and rapid to operate and the analysis results have been proved repeatable and reproducible.It is suitable to determine BTEX in geochemical survey.The efficiency of 1-bromo-4-fluorobenzene as the internal standard for BTEX determination has been investigated,and its mass-peak area linear dependence relations with other single component of BTEX have been identified(all above 0.99).The reproducibility,recovery rate and detection limit of the new method have been tested with real soil,marine sediment and artificially synthesized samples and have achieved satisfying results.The detection limits of the method are below 10 ng/g for each single component of BTEX.