Simultaneous elimination of cationic uranium(vi) and anionic rhenium(vii) by graphene oxide-poly(ethyleneimine) macrostructures: a batch, XPS, EXAFS, and DFT combined study
Simultaneous elimination of cationic uranium(vi) and anionic rhenium(vii) by graphene oxide-poly(ethyleneimine) macrostructures: a batch, XPS, EXAFS, and DFT combined study
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氧化石墨烯-聚乙烯亚胺宏观结构同时消除阳离子铀(vi)和阴离子铼(vii)：批量、XPS、EXAFS和DFT联合研究
DOI：
10.1039/c8en00677f
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发表时间：
2018-09-01
影响因子：
7.3
通讯作者：
Shi, Wei-Qun
中科院分区：
文献类型：
--
作者：
Huang, Zhi-Wei;Li, Zi-Jie;Shi, Wei-Qun
在与环境修复相关的放射性废水处理领域，一个很大的挑战是实现有毒金属阳离子和金属酸根阴离子的同时去除。本文采用自组装方法合成了三维氧化石墨烯负载的乙烯亚胺聚合物复合材料（GO-PEI），并将其用于同时去除水溶液中的阳离子U（vi）和阴离子Re（vii），后者作为Tc（vii）的替代物。GO-PEI复合材料在pH 5.0时对U（vi）和在pH 3.5时对Re（vii）的最大吸附容量分别为629.5和262.6 mg g（-1）。基于傅里叶变换红外光谱（FT-IR）、X射线光电子能谱（XPS）、扩展X射线吸收精细结构（EXAFS）分析和密度泛函理论（DFT）计算，U（vi）的吸附主要归因于与锚定在水凝胶上的大量氨基和含氧基团的配位。相反，Re（vii）的去除与阴离子交换机制相关。此外，GO-PEI已经证明了对超低浓度U（vi）的高度萃取吸附能力。我们的工作可能为创造一种令人兴奋的新材料类别铺平道路，这种材料具有处理核燃料循环放射性流出物的多功能能力。
In the field of radioactive wastewater treatment associated with environmental remediation, a big challenge is to achieve the simultaneous elimination of toxic metal cations and metallate anions. Herein, a three-dimensional (3D) graphene oxide-supported ethyleneimine polymer composite (GO-PEI) was synthesized by a self-assembly strategy and used for the simultaneous removal of cationic U(vi) and anionic Re(vii), which acts as a surrogate for Tc(vii), from aqueous solution. The maximum adsorption capacity of GO-PEI composites at pH 5.0 for U(vi) and at pH 3.5 for Re(vii) was determined to be 629.5 and 262.6 mg g(-1), respectively. Based on Fourier transform infrared (FT-IR) spectroscopy, X-ray photoelectron spectroscopy (XPS), extended X-ray absorption fine structure (EXAFS) analyses, and density functional theory (DFT) calculations, the adsorption of U(vi) is predominantly attributed to the coordination with abundant amino and oxygen-containing groups anchored on the hydrogel. In contrast, the removal of Re(vii) is correlated with the anion-exchange mechanism. In addition, GO-PEI has demonstrated a highly extractive adsorption capability toward U(vi) in ultralow concentrations. Our work may pave the way for creating an exciting new category of material with versatile capabilities for the treatment of radioactive effluent from the nuclear fuel cycle.