气体标准物质研制中液体原料纯度分析方法的建立及应用

Establishment and application of the method for the purity analysis of liquid materials in the preparation of gas reference materials

本文建立了气体标准物质研制过程中测定液体原料纯度的分析方法。该方法通过气相色谱-质谱联用仪(GC-MS)对挥发性有机物如卤代烃以及苯系物等液体原料(卤代烃及苯系物分别以1,1-二氯乙烷和苯为例)中的主成分及杂质化合物进行定性分析。由于碳氢化合物各组分之间在氢火焰离子化检测器上的响应比为定值,通过测定主成分化合物和各杂质化合物的响应比,计算得出各杂质化合物的校正系数,采用校正因子法对液体原料的纯度进行定量分析,该方法相比于直接面积归一法,结果更加准确,不确定度更小。

The method of the purity analysis of liquid materials in the preparation of gas reference materials was established. The method has built a qualitative analysis of principal component and impurity compounds in volatile organic compounds such as halogenated hydrocarbons,BTEX and other liquid materials（ taking 1,1-dichloroethane and benzene as examples） by gas chromatography-mass spectrometry.Because the response of gas chromatography with hydrogen flame ionization detector for different compounds is a fixed value,we could measure the response of the impurity compounds,calculate the response factor of each impurity compounds and obtain the quantitative result of liquid materials.Compared with the area normalization method,this method is more accurate and less uncertain.