基于自制气体循环系统测定全氟异丁腈中杂质成分

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×5 μm）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。

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

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×5 μm). 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.