Institute of Green Chemistry and Chemical Technology, School of Chemistry and Chemical Engineering, Jiangsu University, Zhenjiang, 212013, China; School of Chemistry, Jilin Normal University, Siping, 136000, China.
Institute of Green Chemistry and Chemical Technology, School of Chemistry and Chemical Engineering, Jiangsu University, Zhenjiang, 212013, China.
J Hazard Mater. 2018 Jul 5;353:244-253. doi: 10.1016/j.jhazmat.2018.04.014. Epub 2018 Apr 12.
The increasing amount of europium in aqueous environment from rare earth industry has become a serious environmental challenge. Significant efforts have been focused on ion-imprinting membranes (IIMs) for selective separation of ions from analogues. Based on ion-imprinting technique, we have developed Eu-imprinted nanocomposite membranes (Eu-IIMs) for selectively separating Eu from La, Gd and Sm. Polydopamine (pDA) was previously synthesized on basal membranes to augment the interfacial adhesion. Grapheme oxide (GO) and modified silicon dioxide (kSiO) were synergistically stacked on pDA-modified substrates to form hydrophilic nanocomposite membranes. Ag nanoparticles were modified on the surface to enhance anti-fouling performance. The temperature-controlled selective recognition sites were formed using N-isopropylacrylamide (NIPAm) and acrylamide (Am) as functional monomers as well as europium ions as templates by RAFT (reversible addition-fragmentation chain transfer) method. Large enhanced Eu-rebinding capacity (101.14 mg g), adsorptive selectivity (1.82, 1.57, 1.45 for Eu/La, Eu/Gd, Eu/Sm) and permselectivity (3.82, 3.47, 3.34 for La/Eu, Gd/Eu, Sm/Eu) were achieved on Eu-IIMs with superior regeneration performance. Additionally, the negligible damage of the membranes after buried for 20 d indicated the superior anti-fouling property of the Eu-IIMs. The ion-imprinted nanocomposite membranes synthesized in this work have shown great potentials for selective separation of rare earth ions.
稀土工业中越来越多的铕进入水相环境，这已成为一个严重的环境挑战。人们已经投入大量的努力，致力于研究离子印迹膜（IIM）以实现从类似物中选择性分离离子。基于离子印迹技术，我们开发了用于从镧、钆和钐中选择性分离铕的铕印迹纳米复合膜（Eu-IIM）。先前在基底膜上合成聚多巴胺（pDA）以增强界面附着力。氧化石墨烯（GO）和改性二氧化硅（kSiO）协同堆叠在 pDA 改性基底上，形成亲水性纳米复合膜。在表面修饰银纳米粒子以增强抗污染性能。通过 RAFT（可逆加成-断裂链转移）方法，使用 N-异丙基丙烯酰胺（NIPAm）和丙烯酰胺（Am）作为功能单体以及铕离子作为模板，形成温度控制的选择性识别位点。Eu-IIM 具有 101.14mg/g 的大增强 Eu 再结合容量、吸附选择性（Eu/La、Eu/Gd、Eu/Sm 分别为 1.82、1.57、1.45）和分离选择性（La/Eu、Gd/Eu、Sm/Eu 分别为 3.82、3.47、3.34）以及优异的再生性能。此外，在埋藏 20 天后，膜几乎没有损坏，表明 Eu-IIM 具有优异的抗污染性能。本工作中合成的离子印迹纳米复合膜在选择性分离稀土离子方面具有很大的潜力。
