利用固相萃取和气质联用技术定性空气中的污染物

为了定性兰州地区空气中的有机污染物,用GDX 502和GDX 10l混合吸附剂自行装柱采集空气样品,少量二氯甲烷-乙醚混合有机溶剂淋洗采样管和热解吸浓缩进样装置两种方式进行脱附被吸附物质,最后进行气质联用检测.结果表明用混合吸附剂能更有效吸附各类污染物,在一个样品中最多能检测到380余个物质.样品脱附方法节省有机试剂和时间,避免大量有机溶剂再次污染空气,并且操作简单,所建立的方法有很好的灵敏度,能满足检测空气质量的需要.

Detection of organic pollutants in air with SPE and GC-MS

Air samples were collected from Lanzhou city by mixed sorbents GDX 502 and GDX101 in glass tubes. The air samples eluted by a certain volume of mixed organic solvents and concentrated by N2, or desorbed from sorbents in glass tubes by a device named "heated desorption and concentration injector". The obtained samples were injected into GC-MS and the substances in the samples were separated and qualitative analysis was made of the substances which had higher concentration. The experimental method was easy to operate and as many as 380 substances were detected in a sample. The method showed a better sensitivity and a shorter running time for a sample. Meanwhile, it avoided further pollution in air owing to using less volume of organic solvents.