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High performance liquid chromatography is widely used in environment and analytical chemistry, but often incapable of sample in complex matrix or with low concentration. A preconcentration step is often needed before analysis. Traditional preconcentration techniques, such as liquid liquid extraction（LLE） and solid phase extraion（SPE） both time-consuming and need large volume of organic solvents, which are dangerous for human health and the environment. Recently, analytical method has been oriented towards the development of miniaturized sample, automation, efficent and economical preparation methods. Liquid phase microextraction（LPME） have been deveploped. Meantime, dispersive liquid liquid microextration belong to liquid phase microextration methods, having advantage of using less organic solvent, easy to use, high enrichment and so on. This arcticle used this mehtod, combing with HPLC analysised some matirials in tap water, and assessed the method. The main content of this paper is summarized as follows:（1） In chapter 2, disperisve liquid liuqid microextration combined with HPLC-UV analysis five phenols in tap water, studied and optimised the factors which influence the extration efficient of five phenols, and determined the optimical condition: 4 mL sample solution and 0.75 mL THF was selected as disperive solvent while 30μL carbon tetrachloride as extration solvent, and then the mixture was gentlely shaken and then centrifuged for 5 min at 4000 rmp. Liquid chromatography condition is: 70% methanol containing 0.5% acetic acid as moblie phase, the flow rate is 0.6 mL·min-1,the detection wavelenth is 280 nm, the detection limits of 0-nitrophenol, naphthol, tert-butyl phenol, R-ribaphthol and 2,4,6-Trichlorophenol are 1.03μg·L-1, 1.17μg·L-1, 1.81μg·L-1, 1.03μg·L-1, 1.43μg·L-1, the enrichment factors are 30.9, 51.59, 52.08, 73.32, 64.83.（2） In chapter 3, ultrasoud assissted disperisve liquid liuqid microextration coupled with HPLC-UV analysis five BTEXs in tap water, study and optimise the factors which influence the extration efficient of five BTEXs, and determine the optimical condition: 4 mL sample solution and 0.75 mL methanol was selected as disperive solvent while chloroform of 20μL as extration solvent. Liquid chromatography condition is: 70% methanol as moblie phase, the flow rate is 0.6 mL·min-1,the detection wavelenth is 254 nm, the detection limits of benzene, toluene, styrene, m-xylene, ethlbenzene are 8.37 μg·L-1,6.33μg·L-1, 0.31μg·L-1, 9.68μg·L-1, 10.33μg·L-1, and the enrichment factors are 68.06, 169.89, 114.64, 148.53, 157.32.（3） In chapter 4, disperisve liquid liuqid microextration combined with HPLC-UV analysis five PAEs in tap water, study and optimise the factors which influence the extration efficient of five PAEs, and determine the optimical condition: 4 mL sample solution and 0.75 mL acetonitrile was selected as disperive solvent while 40μL carbon tetrachloride as extration solvent, and then the mixture was gentlely shaken and then centrifuged for 5 min at 4000 rmp. Liquid chromatography condition is: 75% methanol was selected as moblie phase, the flow rate is 0.6 mL·min-1,the detection wavelenth is 280 nm, the detection limits of DEP, DMP, DPrP, DIBP, DBP are 4.46μg·L-1, 4.20μg·L-1, 7.48μg·L-1, 7.48μg·L-1, 3.88μg·L-1. The enrichment factors of five PAEs are 35.16, 72.96, 138.09, 97.06, and 60.38.In a word, the dispersive liquid liquid microextraction method in this article has good extraction efficient, needs little money and takes less time. And is capable of determination of tracing pollutant in water, has a broad prospect of application.
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