脉冲放电氦离子化气相色谱仪在特种气体分析中的应用

The Application of Gas Chromatograph with Pulsed Discharge Helium Ionization Detector to the Analysis of High Purity Gas

脉冲放电氦离子化检测器作为一种高灵敏度检测器,能够检测除氖以外所有气体组分。为了更高效地检测高纯气体中杂质,避免基底气对分析测试结果的影响,一般采用中心切割法将杂质组分从基底气中分离出来。以He、H2、Ar、N2、CH4等高纯特气为例,说明在中心切割技术基础上加装预切柱对5A分子筛色谱柱的寿命以及仪器性能稳定方面有很重要的作用。通过对高纯氨测试结果表明,预切柱中填料的选择对于高纯气中微量氧的准确测定起着至关重要的作用。

Pulsed discharge helium ionization detector（ PDHID） is a kind of detector with high sensitivity. In order to detect impurities in high purity gases effectively,＂heart-cutting＂technique is combined with PDHID to separate minor components from the matrix gas,which can avoid influence in detection from the matrix gas. In this work,the combination of PDHID with ＂heart-cutting＂technique was used to analyze high purity gases of He,H2,Ar,N2,CH4 etc. It can be deduced from the test flow-charts that the existence of pre-column plays a great role in the protection of molecular sieve column and gas chromatograph. Furthermore,the materials that were packed into the micro packed column have a significant influence on the analysis of trace oxygen existed in the high purity gases precisely.