Abstract:

Extraction of the endocrine disrupting compounds (EDCs, such as estriol, bisphenol A, 17α-ethynylestradiol, estradiol and estrone) in water was investigated based on dispersive liquidliquid microextraction procedure with ionic liquid (［C₆MIM］PF₆) as extraction solvent and methanol as dispersive solvent. The distribution coefficients of EDCs between ionic liquid and aqueous phase were compared with those of EDCs between conventional organic solvent and aqueous phase, and the equilibrium molar fractions of EDCs in the system of ［C₆MIM］PF₆water were correlated with the help of the wellknown NRTL equation, and finally, the mechanism of extraction reaction between［C₆MIM］PF₆ and EDCs was discussed as well. The experimental results show that the highest distribution coefficients of EDCs between ［C₆MIM］PF₆ and aqueous phase were D_EE2, followed by D_BPA,D_E1,D_E2 and D_E3 in the studied concentration range, and the distribution coefficients of EDCs in the system of ［C₆MIM］PF₆/water was much higher than that in the system of conventional organic solvent/water, and the molecular interactions among EDCsextraction solventwater were validated by NRTL equation.

Key words: dispersive liquidliquid microextraction, endocrine disrupting compounds, ionic liquid, distribution coefficient, NRTL equation