论文部分内容阅读
目的建立顶空气相色谱法测定工作场所空气中氯化苦的方法。方法用无水乙醇为吸收液,多孔玻板吸收管采集空气中的氯化苦,取吸收液,在温度70℃条件下,顶空加热平衡20 min,采用顶空气相色谱电子捕获检测器测定工作场所空气中氯化苦的浓度。结果氯化苦浓度在0.05μg/ml~2.00μg/ml时具有良好的线性关系,相关系数r=0.999 8,方法检出限为0.000 78μg/ml(进样量为250μl)。最低检出浓度为0.001 7 mg/m3(采样体积为2.25 L,吸收液总体积为5 ml),平均回收率为98.0%~99.0%,相对标准偏差为3.10%~6.34%,样品在4℃冷藏箱内放置,至少可保存10 d。结论本方法操作简便、特异性强、灵敏度高、准确度好、吸收液配制简单,克服了氯化苦与乙醇钠分解反应慢的缺点,缩短了检测时间,特别适用于突发性事件的快速检测。各项指标均符合GBZ/T 210.4—2008的要求,满足工作场所空气中氯化苦测定的要求。
Objective To establish a method for the determination of chloropicrin in the air of workplace by headspace gas chromatography. Methods Chlorobenzene in the air was collected with anhydrous ethanol as absorbing solution and absorbed by porous glass tube. The solution was absorbed at room temperature for 70 min. The headspace was equilibrated for 20 min. The results were determined by headspace electron capture detector Chloropicrin concentration in the workplace air. Results There was a good linear relationship between the concentration of chloropicrin and 0.05μg / ml ~ 2.00μg / ml. The correlation coefficient was 0.999 8. The detection limit was 0.000 78μg / ml (injection volume was 250μl). The minimum detectable concentration was 0.001 7 mg / m3 (the sample volume was 2.25 L, the total volume of the absorption solution was 5 ml). The average recoveries were 98.0% -99.0% and the relative standard deviations were 3.10% ~ 6.34% Store in the cooler for at least 10 days. Conclusion The method is simple, specific, sensitive, accurate and easy to prepare absorbent solution, overcomes the shortcomings of chloropicrin and sodium pentoxide decomposition slow reaction time, shortening the detection time, especially for the rapid Detection. The indicators are in line with GBZ / T 210.4-2008 requirements to meet the chloropicrin determination of air in the workplace requirements.