空气和废气中醛酮污染物的气相色谱测定

DETERMINATION OF ALDEHYDES AND KETONES IN AMBIENT AND POLLUTED AIR BY GAS CHROMATOGRAPHY

以2,4-二硝基苯肼酸性饱和溶液吸收空气和废气中的醛和酮,所形成的腙衍生物用毛细管气相色谱分析。本法预处理回收率在94％以上,最低检测限为0.05—0.1ng,可测定空气和车间空气中挥发性和半挥发性醛和酮类污染物。

The GC determination of aldehydes and ketones in ambient and polluted air was reported. In this paper, 2,4-dinitrophenylhydrazine (2,4-DNPH) in acidic solution was used to absorb aldehydes and ketones in air specifically, and formed 2,4-dinitro-phenylhydrazones, which were determined by GC with a capillary column of SE-54. The 2,4-DNPH absorption solution is effective to separate carbonyls from other organics in gas samples. The GC system can separate nine hydrozones of carbonyls interested with constant recoveries of 94-97%, giving lowest detectable limits of 0. 05-0.1ng. As an application of the method, the carbonyl pollutants were determined in ambient air and gas samples collected from the workshop in a chemical plant, with spiking recoveries of 95-98%, and relative deviations within 5%.