影响12种壬基酚同分异构体液液萃取效率的因素研究

壬基酚是一种新型持久性有机污染物,具有强烈的雌激素效应。近年来壬基酚对水体的污染备受国内外关注,因此实现水体中壬基酚的提取显得尤为重要。目前国内外对于壬基酚萃取效率的研究都是针对总量,对单独异构体萃取效率的研究极少。本文选用传统的液液萃取方法对壬基酚同分异构体进行提取,并进行GC-MS测试,对影响12种壬基酚同分异构体萃取效率的因素进行研究。通过实验比较不同萃取溶剂、萃取溶剂不同用量、不同盐度、不同pH条件下12种壬基酚同分异构体的回收率,研究优化了液液萃取壬基酚的条件。结果表明,选择二氯甲烷作为萃取溶剂,且用量为60 mL,调节水样pH1,氯化钠用量为60 g时,12种壬基酚同分异构体的萃取效率达到88.7%~101.2%,精密度(RSD,n=3)为10.3%~13.6%,检出限9.0~41.4 ng/L。该萃取效率能够达到USEPA规定的回收率在70%~130%范围内,已用于水样中壬基酚的提取。

Study on Impact Factors of Affecting Liquid-liquid Extraction Efficiency of 12 Nonylphenol Isomers

Nonylphenol(NP) which has a strong estrogenic effect, is an emerging persistent organic pollutant (POPs). In recent years, NP has caused widespread attention for its pollution in water at home and abroad. Hence, the extraction of NP in water samples is particularly important. However, the study about extraction efficiency of NP was aimed at the total amount, and single isomers were seldom studied. Liquid-liquid extraction, as the most traditional and easiest method for NP's extraction, was chosen in this study for its simple and cheap equipment. Factors which affect the extraction efficiency of 12 NP isomers were studied by Gas Chromatography-Mass Spectrometry (GC-MS). To improve the extraction efficiency of NP, factors such as the type and dosage of extraction solvent, dosage of NaCl and sample's pH were optimized. Results show that the extraction efficiency of 12 isomers was highest when 60 mL methylene chloride was selected as the extraction agent, and pH<1 and 60 g NaCl was added in the water samples. The extraction rates for 12 NP isomers were in the range 88.7%-101.2% with RSDs (n=3) of 10.3%-13.6% and detection limits of 9.0-41.4 ng/L. The optimized method for 12 NP isomers can achieve an expected extraction effect within 70%-130% by USEPA, and has been used successfully for the extraction of NP in water samples.