Abstract：
A novel magnetic nanoadsorbent (Fe3O4@SiO2@PAA-SO3H) was synthesized by grafting acrylic acid and sulfonic group to Fe3O4@SiO2 using a facile cross-link technology. The adsorbent presented water-stability and biocompatibility in wastewater, which exhibited high-selectivity capture for Pb(II) and Cu(II) of 182.5 mg/g and 250.7 mg/g, respectively, at pH 6.0. Furthermore, the adsorption-desorption processes show that nanoadsorbent still retains high uptake capacity after 6 cycles, revealing structural stability and advanced recycling. Effects from other ions existed weak interference in removal of Pb(II) and Cu(II). Meanwhile, the mechanism was further analyzed from both electrostatic potential (ESP) and average local ionization energy (ALIE) based on the density functional theory (DFT). The results indicate that interaction among nanoadsorbent and heavy metal ions is bridged by oxygen active sites. As the Fe3O4@SiO2@PAA-SO3H adsorbent is a hierarchical, highly water-dispersible and biocompatible adsorbent, it is a potential new treatment option for wastewater.
摘要：
通过简单的交联技术将丙烯酸和磺酸基接枝到Fe3O4@SiO2上，合成了一种新型磁性纳米吸附剂（Fe3O4@SiO2@PAA-SO3H）。该吸附剂在废水中具有水稳定性和生物相容性,对Pb（II）和Cu（II）的高选择性捕获为182.5mg/g和250.7mg/g，分别,在pH6.0。此外，吸附-解吸过程表明，纳米吸附剂在6次循环后仍保持较高的吸收能力，揭示结构稳定性和先进的回收利用。其他离子对Pb(II)和Cu(II)的去除存在微弱干扰。同时,基于密度泛函理论（DFT），从静电势（ESP）和平均局部电离能（ALIE）进一步分析了机理。结果表明，纳米吸附剂与重金属离子之间的相互作用通过氧活性位点桥接。作为Fe3O4@SiO2@PAA-SO3H吸附剂,高度水分散性和生物相容性吸附剂，这是一种潜在的废水处理新选择。
