基于自制气体循环系统测定全氟异丁腈中杂质成分

Determination of impurity components in the perfluoroisobutyrile based on home-made gas-circulating system

建立了基于自制全密闭进样系统的气相色谱-质谱测定全氟异丁腈(C4F7N)商品气中杂质的方法。待测气体在自制的密封系统内稀释并混合均匀,使用在线自动六通阀进样,采用Agilent GS-GASPRO色谱柱(30 m×0.32 mm×5μm)分离,测定了国内某公司(DC公司)和国外某公司(AC公司)的全氟异丁腈绝缘气体的杂质成分。结果表明,全氟异丁腈商品气中含有微量的N2、O2、C3HF7和痕量的C3F6,其中AC公司的C4F7N商品气体中的杂质总含量为0.13%,C4F7N纯度为99.87%;DC公司的C4F7N商品气体中的杂质总含量为0.83%,C4F7N纯度为99.17%,两家公司的C4F7N含量均符合≥99%的标称含量。该法通过对C4F7N绝缘气体组成的测定,为其在电气绝缘输电设备中的应用提供基础成分数据。

A method for the determination of impurity components in perfluoroisobutyrile(C4F7N)gas was established by setting up a sealed pipe gas composition test system comprising an automatic six-way valve and gas chromatography-tandem mass spectrometry(GC-MS)apparatus.C4F7N commercial gases were purchased from an abroad company(AC company)and a domestic Chinese company(DC company).These gases were subjected to qualitative and quantitative analyses by our test system and separated on an Agilent GS-GASPRO column(30 m×0.32 mm×5μm).The results showed that the C4F7N commercial gas contained N2,O2,C3HF7 and a trace amount of C3F6.In the C4F7N commercial gas from the AC company,the total amount of impurities was 0.13%,and the C4F7N content was 99.87%.In the C4F7N gas from DC Company,the total amount of impurities was 0.83%,and the C4F7N content was 99.17%.The C4F7N contents of the gases from both the companies were consistent with the claimed value(≥99%).The determination of the impurities C4F7N can be beneficial for the subsequent study of its insulation performance and thermal stability.