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低浓度惰性气体的色谱分析,由于样品中常存在一些难分离的物质对如He-Ne-H_2、O_2-Ar等不易得到满意的分离,大体上均采用低温条件下进行分离的方法。文献中曾报导在-80℃下用5A分子筛柱分离O_2中微量Ar,在-78℃下用分子筛柱分离He-Ne-H_2。低温操作虽能提高分离效率,但在装置与技术上均带来很大困难,不适用于在一般实验室条件下进行的分析。对一个含有天量H_2、O_2、N_2、CH_4、Co、Co_2和少量He、Ar、Ne的混合气体(其中He、Ar的浓度低于空气中本底,Ne的浓度高于空气中本底几倍)的分析,必须解决He-Ne-H_2和O_2-Ar这两组物质的分离问题。本法选用H_2作载气,使大量H_2峰不致掩盖Ne、Ar峰。He与
Chromatographic analysis of low concentration of inert gas, due to the sample often contain some difficult to separate substances such as He-Ne-H_2, O_2-Ar and other difficult to get satisfactory separation, generally using low temperature separation method. It has been reported in the literature that trace amounts of Ar in O 2 are separated by a 5A molecular sieve column at -80 ° C and He-Ne-H 2 is separated by a molecular sieve column at -78 ° C. Although the low temperature operation can improve the separation efficiency, but the device and technology are very difficult, not suitable for general laboratory conditions for analysis. For a mixed gas containing H_2, O_2, N_2, CH_4, Co, Co_2 and a small amount of He, Ar, Ne (the concentration of He and Ar is lower than the background in the air, the concentration of Ne is higher than the background in the air Times) analysis, the problem of separation of the two groups of substances, He-Ne-H 2 and O 2 -Ar, must be solved. The method uses H 2 as the carrier gas, so that a large number of H 2 peaks do not mask the Ne and Ar peaks. He and