锆离子印迹聚合物分离锆和铪的研究

Separation of Zirconium and Hafnium Using Zirconium Ion-Imprinted Polymers

以锆(Ⅳ)离子为印迹离子,磷酸三丁酯(TBP)为络合剂,4-乙烯基吡啶和苯乙烯为功能单体,二乙烯基苯为交联剂,采用本体聚合法制备了锆离子印迹聚合物(Zr-IIPs)和控制聚合物(CPs)。用1:1盐酸将锆离子印迹聚合物中的锆离子洗脱,释放出印迹空腔。对Zr-IIPs和CPs进行了FT-IR和XRD分析表征。研究了pH及吸附平衡时间对锆离子印迹聚合物吸附性能的影响,通过批组实验得到达到锆离子印迹聚合物最大吸附量为619.334μg·g-1,吸附所需时间大约是20 min。对于锆离子印迹聚合物,Zr(IV)/Ti(IV)和Zr(IV)/Hf(IV)的相对选择系数分别为2.11和1.43,而控制聚合物的则分别是1.58和1.15。

Zirconium（Ⅳ） ion-imprinted polymers（Zr-IIPs） and control polymers（CPs） were prepared by bulk polymerization with tributyl phosphate as the complexing agent,4-vinylpyridine and styrene as the functional monomers and divinylbenzene as the crosslinking agent wherein the zirconium（Ⅳ） ion is the print ion and is used to form the imprinted polymer.The zirconium ion was removed from the polymer by leaching the polymer particles with 1：1 HCl which washes away the zirconium ions in the polymer and leaves cavities on the polymer particles.The prepared Zr-IIPs and CPs were characterized by FT-IR and XRD,respectively.The effects of pH and equilibrium adsorption time on the zirconium（Ⅳ） ion adsorbability of Zr-IIPs was investigated.The experimental results show that the maximum amount of Zr ions can be adsorbed on the prepared imprinted polymer is 619.334 mg×g-1 and the time needed for the extraction of the Zr ions by batch method is about 20 min.For Zr-IIPs,the relative selectivity factor values of Zr（Ⅳ）/Ti（Ⅳ） and Zr（Ⅳ）/Hf（Ⅳ） are 2.11 and 1.43,respectively,and for CPs,the corresponding values are 1.58 and 1.15,respectively.