直接进样的气相色谱法测定大气中烃类

The determination of hydrocarbons in air by gas chromatography through direct injection

以脱烃空气作载气,由直接进样的气相色谱法测定大气中的烃类;采用大体积进样(15ml),提高了检测极限;用反吹技术使得一次进样就能同时测出甲烷、乙炔、乙烷和总烃(以下用丙烷代替总烃)。此方法不同于传统的吸附-脱附法,能简单、直接、迅速、准确地进行测定,其最低检测量为0.05ppm,最大变异系数为4.2%。

A chromatographic method was described for the determination of methane, ethane , acetylene and the total amount of other hydrocarbons in air. Through the use of a large sample volume (15ml) , combined with carrier gas back-flushing, all components can be determined in one injection. This technique is simple, more accurate and less time-consuming as compared with the conventional methods. The detection limit was 0. 05ppm(50ppo) and the standard deviation was 4. 2%.