气相色谱法测定空气中对硝基苯胺

Gas Chromatography for Determination of P-Nitroaniline in Air

本文选用硅胶管收集空气中的对硝基苯胺,经乙醇解吸后,取样溶注入气相色谱仪氢火焰离子鉴定器测定。硅胶管对对硝基苯胺的吸附效果良好,穿透容量为22.16mg/200mg硅胶,现场采样效率在不同浓度时均为100％,乙醇对对硝基苯胺的解吸效率为90％以上。样品在硅胶管中稳定时间长,至少能保存7天。方法的重现性良好,在不同浓度时的变异系数为1.2～1.6％。若采样5L,最低检出浓度为0.5mg/m^3。空气中与对硝基苯胺共存的苯胺、二甲基苯胺在本方法条件下不干扰测定。

This paper describes the method of airborne P-Nitroaniline determination. The method uses sil- icagel tube to collect, after desorption of alcohol solvent, the airborne P-Nitroaniline and the aliquot of the solution is injected into the GC-FID for me- asurement. Breakthough volume of the absorber tube is 22.16mg/200mg silicagel. Sampling efficiency with various concentration remains at 100%. The desorption efficiency of the solvent (CH_3 CH_2 OH) is above 90%. Good stability of the silicagel tube samples stored at room temperature for up to 7 days is also achieved. This method has good repe- atability and the CV at different concentration is 1.2%～1.6%. The minimum detection concentration of this method is 0.5mg/m^3 when sampling volume is 5 L. Under this condition, airborne aniline and dimethyl-phenylamine dose not cause interference to the determination.