铁(Ⅱ)离子印迹聚合物对稀土中铁的识别性能研究

Recognizing properties of ionic imprinted polymer towards Fe(Ⅱ) in rare earth

通过γ-氯丙基三甲氧基硅烷的媒介,将功能大分子聚乙烯亚胺(PEI)偶合接枝到硅胶微粒表面,形成了接枝材料PEI/SiO2;以Fe2+为模板离子,乙二醇二缩水甘油醚为交联剂,对化学键合在硅胶表面的PEI大分子链进行了离子印迹,制备了Fe2+印迹材料IIP-PEI/SiO2。采用静态法研究了IIP-PEI/SiO2对Fe2+的结合特性。实验结果表明,Fe2+印迹材料IIP-PEI/SiO2对Fe2+具有强的结合亲合性与优良的识别选择性。IIP-PEI/SiO2对Fe2+的结合容量可以达到1.98mmol/g,结合行为服从Freundlich单分子层吸附。相对于Ce3+与Pr3+离子,IIP-PEI/SiO2对Fe2+离子的选择性系数分别为25.57与20.63。另外,IIP-PEI/SiO2具有良好的重复使用性能。

Polyethyleneimine （PEI） was grafted onto the surface of silica gel particles through the coupling effect of γ-chloropropyl trimethoxysilane （CP）, and PEI/SiO2 was prepared. Then the ionic imprinted polyethylenei- mine on the surface of silica gel was prepared using Fe^2＋ as template ions and ethylene glycol diglycidyl ether （EGDE） as crosslinking agent and ionic imprinted material IIP-PEI/SiO2 was obtained. The binding properties of IIP-PEI/SiO2 for Fe^2＋ were researched using batch and methods. The experiment results show that the ionic imprinted material IIP-PEI/SiO2 possesses strong binding affinity and specific recognition selectivity property for Fe^2＋. The binding capacity could reach to 1.98mmol/g, and binding isotherm data greatly obey the Freun dlich model. The relative selectivity coefficients relative to Ce3＋ and Pr3＋ are 25.57 and 20.63, respectively. Besides, the IIP-PEI/SiO2 can be regenerated easily and IIP-PEI/SiO2 possesses better reusability.