School of Chemistry, University of the Witwatersrand. P/Bag 3, WITS 2050, Johannesburg, South Africa.
Water Sci Technol. 2012;65(4):728-36. doi: 10.2166/wst.2012.911.
Ion imprinted polymer material (IIP) was prepared by forming ternary complexes of uranyl imprint ion with 1-(prop-2-en-1-yl)-4-(pyridin-2-ylmethyl)piperazine and methacrylic acid followed by thermal copolymerization with ethylene glycol dimethacrylate as the cross-linking monomer in the presence of 1,1'-azobis(cyclohexanecarbonitrile) initiator and 2-methoxy ethanol porogenic solvent. HCl solution (5 mol/L) was used to leach out the uranyl template ion from the IIP particles. Similarly, the control polymer (CP) material was also prepared exactly under the same conditions as the IIP but without the uranyl ion template. Various parameters such as solution pH, initial concentration, aqueous phase volume, sorbent dosage, contact time and leaching solution volumes were investigated. SEM, IR and BET-surface area and pore size analysis were used for the characterization of IIP and CP materials. The extraction efficiency of the IIP and CP was compared using a batch and SPE mode of extraction. The optimal pH for quantitative removal is 4.0-8.0, sorbent amount is 20 mg, contact time is 20 min and the retention capacity is 120 mg of uranyl ion per g of IIP. The IIP prepared demonstrated superior selectivity towards coexisting cations and therefore it can be used for selective removal of uranium from complex matrices.
离子印迹聚合物材料（IIP）是通过形成铀印迹离子与 1-(丙烯-2-基）-4-(吡啶-2-基甲基）哌嗪和甲基丙烯酸的三元配合物，然后在 1,1'-偶氮双（环己甲腈）引发剂和 2-甲氧基乙醇致孔溶剂的存在下，与乙二醇二甲基丙烯酸酯进行热共聚而制备的。HCl 溶液（5mol/L）用于从 IIP 颗粒中浸出铀模板离子。同样，在与 IIP 完全相同的条件下准确制备了对照聚合物（CP）材料，但没有铀离子模板。研究了各种参数，如溶液 pH 值、初始浓度、水相体积、吸附剂用量、接触时间和洗脱溶液体积。SEM、IR 和 BET 表面积和孔径分析用于 IIP 和 CP 材料的表征。使用批处理和 SPE 提取模式比较了 IIP 和 CP 的萃取效率。定量去除的最佳 pH 值为 4.0-8.0，吸附剂用量为 20mg，接触时间为 20min，每克 IIP 的保留容量为 120mg 铀离子。制备的 IIP 对共存阳离子表现出优异的选择性，因此可用于从复杂基质中选择性去除铀。
