顶空气相色谱法同时测定水中15种卤代烃

Simulations determination of 15 halogenated hydrocarbons in water by headspace- gas chromatography

目的建立同时测定水中15种卤代烃的顶空气相色谱方法。方法水中的微量卤代烃经顶空气液分配后,用DB-624宽口径毛细管柱进行分离,对色谱条件、水浴平衡温度、平衡时间、气液相体积比等影响因素进行研究和优化。结果在所建立的最佳实验条件下能有效地分离水中的15种卤代烃。各组分的保留时间稳定,峰形对称,15种卤代烃能达到基线分离,线性范围能满足测定要求。标准曲线的相关系数为0.998 7~0.999 6,各组分的检出限为0.01μg/L^2.22μg/L,精密度RSD为2.04%~2.56%,加标回收率为88.6%~103.8%。同一样品瓶重复进样最多只能3次;适宜的气液体积比为1∶2。结论本法准确、简便,适合水中15种卤代烃的同时检测分析。

Objective To establish a gas chromatographic method for detection of 15 halogenated hydrocarbons in water. Methods The target hydrocarbons in water sample were separated with DB- 624 capillary column after allotting with head gas liquid. Parameters affecting efficienciessuch as the chromatographic conditions,the equibilium temperature,the equibilium time and the ratio between the liquid and the gaseous phase were optimized. Results In the optimum condition,enable to effectively separate and determinate 15 halogenated hydrocarbons in water. The retention time of 15 compounds was stable and their peak profiles were also symmetric. The baselines of 15 halogenated hydrocarbons separated well,the linear range could meet the measurement requirements. The correlation coefficient of the standard curve was among 0. 998 7- 0. 999 6. The lowest determination limit was among 0. 01 μg / L- 2. 22 μg / L,the rate of recovery was among 88. 6%- 103. 8% and RSD were 2. 04%-2. 56%. The sampling time can not surpass three times and suitable volume rate between gas and liquid was 1 ∶2. Conclusion This method is simple,rapid,sensitive and accurate. It is suitable for the determination of 15 halogenated hydrocarbons in water.