双柱串联-便携式气相色谱法测定室内空气中苯系物

摘要

Determination of benzene series(BTEX) in indoor air by tandem double column–portable gas chromatography was developed. The indoor air samples were collected 100 s by Tenax adsorbent for instrument in 0.5 L/min flow, and the instrument was quickly heated to 400℃for thermal desorption injection, and the seven kinds of BTEX were detected by micro argon ionization detector(MAID). The chromatographic conditions were as follows: MXT–200 and MXT–WAX metal capillary chromatographic column in series was used, the column temperature was 90℃, column pressure was 103 425 Pa. Under this condition, the separation effect was best, and the operation time was short. The mass concentration of each compounds and the square root of peak area had good linear relationship in the range of 19.26–306.7 g/m3, and the correlation coefficients were more than 0.995. The detection limit was 6.40–15.9μg/m3, the recovery rate of the blank addition of each component was 92%–114%, and the relative standard deviation of determination results was 6.1%–13.7%(n=6). The method is rapid, accurate and convenient.%建立双柱串联–便携式气相色谱测法定室内空气中苯系物的方法。利用仪器内部自带的Tenax吸附剂在0.5 L／min流量下采集空气样品100 s，然后仪器迅速升温至400℃左右，对吸附剂进行热解吸进样，以微亚离子检测器(MAID)对室内空气中7种苯系物进行测定。结果表明，色谱条件为MXT–200／MXT–WAX金属毛细管柱串联色谱柱，柱温90℃，柱压103425 Pa时，分离效果最好，且运行时间短。各组分在19.26～306.7μg／m3范围内与色谱峰面积的平方根线性关系良好，相关系数r大于0.995。方法检出限为6.40～15.9μg／m3，空白加标回收率为92%～114%，测定结果的相对标准偏差为6.1%～13.7%(n=6)。采用双柱串联便携式气相色谱法测定室内空气中苯系物具有快速、准确、方便等优点。