液液萃取气相色谱法测定饮用水中三氯乙醛

Determination of trichloroaldehyde in drinking water using liquid-liquid extraction and gas chromatography

目的建立液液萃取气相色谱法测定饮用水中三氯乙醛。方法通过优化萃取溶剂、pH、盐析试剂、内标物等提取试验以及色谱参数,然后利用优化后的参数进行方法验证,并与国标方法进行比对分析。结果在优化后的萃取条件及仪器分析条件下,三氯乙醛在0.20～20.0μg/L范围内,具有较好的线性相关性,相关系数r>0.999;方法检出限为0.030μg/L,纯水与管网水加标浓度为1.0μg/L时的回收率分别为94.8%和93.7%,相对标准偏差分别为2.9%和3.4%,纯水与管网水加标浓度为16.0μg/L时的回收率均为101%,相对标准偏差分别为1.0%和1.3%。配对样本分析显示该方法对实际水样的测定值总体低于国标方法。结论该方法灵敏、准确,适合饮用水中三氯乙醛的检测。

OBJECTIVE To establish a liquid-liquid extraction and gas chromatography method for the determination of trichloroacetaldehyde in drinking water.METHODS Chromatography parameters and extraction parameters,such as extraction solvent,salting out reagents,internal standards and pH were tested and selected.Using the optimized parameters,methods validation and comparison with the national standard examination method was also conducted.RESULTS Employing the optimized extraction and instrumental analytic parameters,good correlation coefficient was obtained in the linear range of 0.20-20.0μg/L,with r greater than 0.999.The methods detection limit was 0.030μg/L.When spiked concentration was 1.0μg/L for pure water and tap water,the recoveries were 94.8%and 93.7%,respectively,and relative standard deviation was 2.9%and 3.4%,respectively.When spiked concentration was 16.0μg/L for pure water and tap water,the recoveries were both 101%and relative standard deviation was 1.0%and 1.3%,respectively.Paired samples t test showed that the result obtained with this method were generally lower than that acquired from the national standard examination method.CONCLUSION This method is sensitive and accurate,and it is suitable for the determination of trichloroaldehyde in drinking water.