气相色谱法测定高压气体中低浓度苯及甲苯含量

Determination of low-concentration benzene and methylbenzene of in high-pressure gas by gas chromatography

建立高压气体中苯及甲苯的气相色谱检测法。高压气体经还原至常压,使用溶剂解吸型活性碳管吸附,放置一段时间后使用二硫化碳解吸,并使用气相色谱分析。使用该方法测定苯及甲苯的检出限分别为0.19μg/mL及0.15μg/mL,且精密度高,适合作为高压气体中低浓度苯及甲苯的检测。

In this study,we developed a method to detect benzene and methylbenzene in high-pressure gas using gas chromatography. After returning the gas sample to normal pressure,we adopted the solution-desorption activated carbon tubes to absorb the sample,and then carbon disulfide to desorb the activated carbon after standing the tubes for some time. Then the samples were analyzed by gas chromatography. The detection limits of benzene and methylbenzene by this method were 0. 19 μg/mL and 0. 15 μg/mL,respectively. This method had high accuracy and was suitable for the determination of low-concentration benzene and methylbenzene of in high-pressure gas.