顶空气相色谱法测定水中苯系物实验研究

Determination of BTEX in Water by the Headspace-Gas Chromatography

采用顶空气相色谱法对水中苯系物的测定方法进行了研究。在研究过程中讨论了盐,顶空平衡温度和平衡时间等因素对测定结果的影响。实验结果表明无机盐的加入可以提高苯系物的响应值,顶空平衡温度和平衡时间分别为60℃和50 min时为最优的实验分析条件。在此实验条件下,苯系物各组分回归方程的线性相关性较为显著。方法的检出限在2.5~5.9μg/L,加标回收率为93.8%～96.8%,相对标准偏差小于14.7%。该方法对于水中苯系物的测定准确、快捷、重现性好。

A method for quantitative determination of volatile BTEX in water with headspace gas chromatography was discussed in the paper.The parameters that affect the extraction efficiency such as the effect of salt addition,equilibration temperature and equilibration time were studied in details.The results showed that the addition of inorganic salts could improve the response of BTEX.Extraction efficiency reached a maximum when headspace equilibration temperature and time were at 60 ℃ and 50 minutes,respectively.Under the optimum experimental conditions,the linearity of the regression equations was excellent.The results of detection limits for the studied compounds showed that the limits of detection were in the range of 2.5 to 5.9 μg/L.The recoveries were 94.0%～96.8%.The relative standard deviations(RSD%) was less than 14.7%,which demonstrated a good method repeatability and an acceptable precision.The analysis results showed that the method is simple,rapid,accurate and practical for the determination of BTEX in water samples.