气相色谱法测定空气中苯系物的热解吸和溶剂解吸比对研究

针对测定工作场所空气中苯系物的标准方法热解吸和溶剂解吸．气相色谱法在实际应用中存在的问题，分别考察和比对了这两种方法，特别对影响热解吸效率的因素进行了详细研究，发现改善热解吸方式能提高活性炭管的合格率和热解吸效率；不同温度下需要的解吸时间不同，延长热解吸时间有利于提高样品解吸率；并对标准方法GBZ／T160．42-2004提出了相应的改进措施。

Comparison study on thermal desorption and solvent desorption methods for determination of alkyl benzenes in indoor air by gas chromatography

The standard methods for determination of alkyl benzenes in the air, thermal desorption gas chromatography and solvent desorption gas chromatography, have some problems in practice which affect the accuracy, repeatability and application. In order to improve them, several performance indices for the two methods have been examined and compared in this paper. Specific study has been done on the factors that would affect the desorption efficiency of thermal desorption. It was found that to improve the desorpfion way would increase the eligibility ratio and desorption efficiency of activated carbon tube. Different time was required for desorption under various temperature.Prolongation of the desorption time was beneficial to full dedorption.Also, the standard thermal desorption methods were found to be well accord with analytical results of benzene, but not with that of toluene or xylene.Some suggestions were given with reference to the standard for indoor air.