色谱-质谱联用法测定三氟化氮中痕量六氟化硫

Determination of Trace Sulfur Hexafluoride in Nitrogen Trifluoride Gas by Gas Chromatography-Mass Spectrometry

用选择离子监测 (SIM)方式测定了高纯三氟化氮 (NF3)气体中痕量六氟化硫 (SF6 )。采用 pora PLOT Q毛细管色谱柱φ3 0 m× 0 .3 2 mm× 5μm,选择 m/ z 1 2 7作为定量离子 ,同时考察了 NF3工艺气物流对所选离子的测定干扰情况。在浓度为 2 .0～ 1 0 0 μL/ L范围内 ,峰面积与浓度呈线性关系 ,线性相关系数 r=0 .9996。最低检测限为 0 .2μL/ L,平均加标回收率为 92 .70 %～ 97.0 4 % ,日内测定结果的 sr<4 .1 7% ,日间测定结果的 sr<5 .3 3 %。

The trace sulfur hexafluoride in high pure nitrogen trifluoride gas was determin by selective ion monitor (SIM) mode. The analysis is carried out on a poraPLOT Q capillary column (5 μm×0.32 mm×30 m) and QP5000 GC/MS. The quantitative selected ion is m/z 127. The interferece to the determination of selected ion was studied. The linear range is from 2.0 to 100 μL/L with relative coefficient of 0.9996. The mininum detection limit is 0.2 μL/L. The average recovery is 92.70%~97.04%. The intra-day and inter-day relative standard deviation(s r) of SF 6 is less than 4.17% and 5.33%, respectively.