离子液体液-液萃取-高效液相色谱测定水中酚类化合物

Analysis of Phenolic Compounds by Ionic Liquid Based Liquid-Liquid Extraction Coupled with High Performance Liquid Chromatography

建立了离子液体1-丁基-3-甲基咪唑六氟磷酸盐([C4mim][PF6])液-液萃取-高效液相色谱测定水中酚类化合物的方法。研究了水相pH值、萃取时间、水相体积及盐的浓度对萃取的影响。最佳萃取条件分别为:水相pH值为5,萃取时间为40min,水相体积为60mL。对比了离子液体对1-辛醇对苯酚、4-硝基苯酚、2-硝基苯酚、2,4-二甲基苯酚和双酚A的富集效率。在最佳条件下,离子液体对5种酚的富集倍率在9～151之间,方法对苯酚、4-硝基苯酚、2-硝基苯酚、2,4-二甲基苯酚和双酚A的检出限分别为:2.0、0.9、0.3、1.8和1.1μg/L。将该方法应用于自来水、河水、湖水和污水的检测,回收率为87.9%～109.9%。

A method was investigated for the simultaneous determination of phenols in water by ionic liquid 1-butyl-3-methylimidazolium hexafluorophosphate （ [ C4 mim ] [ PF6 ] ） based liquid-liquid extraction coupled with high performance liquid chromatography. Some conditions that might affect the extraction efficiency such as pH value of aqueous phase, extraction time, volume of aqueous phase and salt concentration were optimized. The results indicated that the optinal conditions were pH 5.0, 40 min of extraction time, 60 mL of aqueous phase and no added salt, respectively. The enrichment factor of [ C4mim] [ PF6 ] for phenol, 4-nitro- phenol, 2-nitrophenol, 2,4-dimethylphenol and bisphenol A were compared with 1-octanol. Under the optimal conditions, the enrichment factor of ionic liquid for the five phenols were in the range of 9 - 151. The detec- tion limits of phenol, 4-nitrophenol, 2-nitrophenol, 2,4-dimethylphenol and bisphenol A were 2.0, 0.9, 0. 3, 1.8 and 1. 1μg/L （S/N = 3）, respectively. The proposed method was applied to the determination of the five phenols in tap, river, lake and waste water. Recoveries of the five phenols were in the range of 87.9% - 109.9%.