针式萃取-气相色谱联用测定加油站附近空气中苯系物

摘要

The contents of benzene homologues, including methylbenzene, ethylbenzene, o, p and m-xylene in air near petrol station were determined by GC. The benzene homologues in sample were collected and enriched by needle trap extraction, and thermo-desorbed and determined by GC. SE 30 capillary chromatographic column （30 m）〈0. 25 mm, 0. 33μm） was used for separation, and hydrogen flame ionization detector was adopted for detection. Values of detection limit （aS/N） of the method found were in the range of 0. 36-1.32μg. Tests for recovery and precision were made by standard addition method, values of recovery and RSD＇s （n=5） found were in the ranges of 94. 1%-104. 5% and 4. 9%-8. 7%.%提出了气相色谱法测定加油站附近空气中苯系物（甲苯、乙苯、邻二甲苯和间，对二甲苯）含量的方法。采用针式萃取装置对样品中的苯系物进行收集和富集，然后经气相色谱热解吸，采用SE30毛细管色谱柱（30m×0．25mm，0．33μM）进行分离，用氢火焰离子化检测器进行测定。方法的检出限（3S／N）在0．36～1．32μg之间。方法的回收率在94．1％～104．5％之间，相对标准偏差（n=5）在4．9％～8．7％之间。