烯基离子液体为单体的磁性分子印迹聚合物及其用于酚类化合物的萃取和检测

Magnetic molecularly imprinted polymer using vinyl-based ionic liquid as monomer and its application in extraction and determination of phenolic compounds

以3-（甲基丙烯酰氧）丙基三甲氧基硅烷修饰的Fe3O4为载体,乙二醇二甲基丙烯酸酯为交联剂,4-硝基苯酚为模板分子,烯基离子液体1-乙烯基-3-乙基咪唑四氟硼酸盐为功能单体制备了磁性分子印迹聚合物（IL-MMIP）,采用透射电镜、红外光谱和磁强计对磁性分子印迹聚合物进行表征,结果表明磁性载体表面成功地包覆了分子印迹聚合物层。IL-MMIP对4-硝基苯酚的吸附在10 min达到平衡,最大饱和吸附量达到20.98μmol/g。对比磁性非印迹聚合物,IL-MMIP对4-硝基苯酚具有较高的选择吸附性能。IL-M M IP萃取-高效液相色谱法对4-硝基苯酚、2-硝基苯酚、苯酚、间甲酚等4种酚类化合物进行检测,检测限在0.2-1.7μg/L。方法应用于自来水、嘉兴南湖水、焦化厂废水等实际样品中酚类化合物的检测,加标回收率在85.7%-100.5%。

Ionic liquid-based molecularly imprinted polymer （ IL-MMIP ） was prepared using 3-methacryloxypropyl trimethoxysilane-functionalized Fe3O4as the support matrix, ethylene glycol dimethacrylate as the cross-linker agent, 4-nitrophenol （4-NP） as the template molecule, and vinyl-based ionic liquid of 1- vinyl-3-ethylimidazolium tetrafluoroborate as the functional monomer. IL-MMIP was characterized with transmission electron microscopy, Fourier transform infrared spectrometer, and magnetometer, which demonstrated that the imprinted polymer layer was successfully coated onto the surface of Fe3 04. The result showed that IL-MMIP reached the adsorption equilibrium for 4-NP within 10 min. The maximum adsorption capacity of IL-MMIP was obtained as 20.98μmol/g. Compared with the magnetic non imprinted polymer, IL- MMIP exhibited higher selectivity adsorption for 4-NP. The proposed method of IL-MMIP extraction coupled with high performance liquid chromatography was used for detecting phenolic compounds. The limits of detection were found to be in the range of 0. 2 to 1.7 μg/L. The recoveries of four phenolic compounds in actual samples including tap water, Jiaxing nanhu lake and coking-plant wastewater were found to be between 85.7% and 100.5%.