气相色谱法测定水中九种卤代乙酸类化合物研究

建立了液-液萃取气相色谱-双柱-双检测器法测定水中九种卤代乙酸类化合物的检测方法.40 ml水样经4 ml甲基叔丁基醚两次萃取,萃取液经10%硫酸-甲醇50℃衍生后,用气相色谱电子捕获检测器检测.方法检出限为0.6~1.0μg/L,加标回收率75.9%~111%,6次测定的相对标准偏差≤16%.两次萃取显著提高了一氯乙酸和一溴乙酸的回收率,双柱-双检测器有效排除实际样品中假阳性结果,检测结果更准确可靠.

Determination of Haloacetic Acids in Water by Gas Chromatography Method

The analytical method for determining haloacetic acids in water by gas chromatography-dual column-dual detec-tor was found. A 40-ml water sample was extracted twice with 4 ml MTBE. The extract was derived with 10% sulfuric acid in methanol in 50℃ water bath. At last, the treated sample was detected with GC-ECD by internal standard method. The results demonstrated that the method detection limits for 9 HAAs were 0. 6~1. 0μg/L, the recoveries in three real samples were within 75. 9% ~111%. The RSD of precisions were less than 16%. The method of extraction twice is highly improved recovery of MCAA and MBAA. Dual column-dual detector determination can exclude the false positive results in samples, and it can make results more accurate and reliable.