一种新型的用于萃取铷的冠醚功能化磁性固相纳米材料

A Novel Crown-ether-functionalized Magnetic Solid-phase Nanomaterial for Extracting Rubidium

本研究成功制备了一种新型的用于萃取铷的冠醚功能化磁性固相纳米材料(CFE)。通过溶剂热法合成了Fe_(3)O_(4)纳米颗粒磁核,利用3-氨丙基三乙氧基硅烷在碱性环境下的酯水解反应,在磁核表面包覆SiO_(2)并修饰氨基,制备了Fe_(3)O_(4)@SiO_(2)-NH_(2)中间产物,再利用4′-羧基苯并-18-冠6-醚上的羧基与修饰在Fe_(3)O_(4)@SiO_(2)-NH_(2)表面的氨基在1-乙基-(3-二甲基氨基丙基)碳二亚胺盐酸盐的催化下发生酰胺化反应,将该冠醚修饰在中间产物的表面,制备了CFE新型材料。分析了Fe_(3)O_(4)、Fe_(3)O_(4)@SiO_(2)-NH_(2)、CFE的微观形貌、磁化性质、X射线衍射性质、红外吸收性质、元素组成,佐证了材料被成功制备,验证了CFE对Rb^(+)的萃取能力,研究了溶液pH对Rb^(+)萃取效果的影响。结果表明,室温下萃取30 min,在pH为13时CFE对Rb^(+)具有最佳的萃取效果,萃取率为90.0%。

In this study,a novel crown-ether-functionalized nano magnetic solid-phase extractant(CFE)for extracting Rb^(+)was successfully prepared by the following three steps.First,the magnetic core of Fe_(3)O_(4) nanoparticles was synthesized by a solvothermal method.Second,the SiO_(2)-NH_(2) group was coated on the surface of the magnetic core to prepare an intermediate product of Fe_(3)O_(4)@SiO_(2)-NH_(2) by ester hydrolytic reaction of(3-aminopropyl)triethoxysilane in an alkaline environment.Third,the targeted functional group of crown ether was then modified on the surface of the intermediate product to prepare a novel CFE extractant by an amidation reaction between the carboxyl group in 4′-carboxybenzo-18-crown 6-ether and the amino group on Fe_(3)O_(4)@SiO_(2)-NH_(2) under the catalysis of N-(3-Dimethylaminopropyl)-N′-ethylcarbodiimide hydrochloride.Then,the characteristics of micro morphology,magnetization,X-ray diffraction,infrared absorption,and elemental composition of the Fe_(3)O_(4),Fe_(3)O_(4)@SiO_(2)-NH_(2) and CFE were analyzed,which had lent support to the successful preparation of these materials.The extraction ability for Rb^(+)of this novel CFE material was verified.Moreover,the effect of solution pH on Rb^(+)extraction rate was explored,and the results showed that CFE had a best extraction rate of 90.0%for Rb^(+)at the pH 13(at room temperature,extracting for 30 minutes).