大气中痕量有机物的GC／MS分析与研究  

Analysis and Research of Trace Organic Gases in Atmosphere by GC/MS

作　　者：王跃思[1] 王明星[1] 刘广仁[1] 施钧慧[1] 

机构地区：[1]中国科学院大气物理研究所,国家环境分析测试中心

出　　处：《质谱学报》1996年第4期25-33,共9页Journal of Chinese Mass Spectrometry Society

摘　　要：本文介绍用一套自制的大气浓缩装置结合色谱／质谱，自动采样和分析城市污染大气及远离城市的自然本底大气中痕量有机物的过程。分析的目标化合物主要是烃类化合物（ＨＣＳ）和氯氟烃类化合物（ＨＣＦＣｓ）。用二级浓缩进样系统浓缩５００～１０００ｃｍ３空气样品，检测限可达２０ＰＰｔｖ（１０－１２摩尔比）。在玻璃微球填充的微型柱中浓缩的样品经加热被吹扫转移到色谱柱柱头，然后冷柱头以５０℃／ｓ的加热速度使浓集在其中的空气样品迅速汽化被“注射”到色谱柱中。用质谱检测每个被分离的有机化合物并用计算选择的特征离子峰面积法对其进行定量分析。An automated Air Sample Concentrator/Gas Chromatograph/Mass Spectrometer(ASC/GC/MS)is described for the urban and field atmosphere monitoring of trace organic gases,included hydrocarbons(HCs),hydrofluorocarbons(HFCs) and hydrochlorofluorocarbons(HCFCs).Detection limits 20pptv are achieved by concentration of 500￣100 cm3 air sample onto a two-stage cryotrap.The enriched air sample is thermally desorbed by direct ohmic heating of the glasss beadfilled microtrap and quickly transported to the head of GC colmn cryofocussing there.The cooled column head is heated in a high speed of 50℃/s and the air sample is'injected' to the column.Individual organic compounds are determined by selected ion masses for quantitation.The all system is designed to operate automatically at an atmospheric monitor or research centres providing about 1.5 hour kreplicate calibration analyses.

关 键 词：大气 有机物 色谱 质谱 

分 类 号：X132[环境科学与工程—环境科学]