National Demonstration Center for Experimental Comprehensive Chemical Engineering Education, Shanxi Province Key Laboratory of Functional Nanocomposites, School of Chemical Engineering and Technology, North University of China, Taiyuan, Shanxi, 030051, PR China.
National Demonstration Center for Experimental Comprehensive Chemical Engineering Education, Shanxi Province Key Laboratory of Functional Nanocomposites, School of Chemical Engineering and Technology, North University of China, Taiyuan, Shanxi, 030051, PR China.
Environ Res. 2021 May;196:110375. doi: 10.1016/j.envres.2020.110375. Epub 2020 Oct 30.
High background electrolyte and natural organic matter are favorable to migration of hazardous radionuclides in geochemical repository. Herein, Ca-Mg-Al layered double hydroxide coated onto graphene oxide (Ca-Mg-Al LDH/GO) composites were successfully synthesized, characterized and adopted to decontaminate Eu(III) and fulvic acid (FA) under diverse experimental conditions. Diverse concentration gradients and different addition sequences on Eu(III) and FA were also obtained, which revealed different interaction mechanisms. The experimental results displayed that the coexistence of FA and Eu(III) respectively promoted adsorption performance of Eu(III) and FA under the ternary systems. The acquired Ca-Mg-Al LDH/GO composites were adopted to remove Eu(III) and FA, which further illustrated excellent chemo-physical stability and adsorption capacity of 1.12 × 10 mol/g and 3.54 × 10 mol/g, respectively. The remarkable adsorption performances of Ca-Mg-Al LDH/GO were confirmed through kinetic procedures and depending-temperature isotherms, illustrating that the kinetics processes were simulated using pseudo-second-order pattern, and the adsorption isotherms were splendidly simulated using Langmuir pattern. XPS spectrum analysis revealed that these containing oxygen groups took significant part in the restricting of Eu(III) and FA onto the surfaces of Ca-Mg-Al LDH/GO composites. In view of experimental results, the Ca-Mg-Al LDH/GO composites can be as potential adsorbents with availably recycled reusability for the decontamination of Eu(III) and FA from nuclear fuel partition or nuclear wastewater systems.
高背景电解质和天然有机物有利于危险放射性核素在地质处置库中的迁移。在此，成功合成、表征了负载在氧化石墨烯（GO）上的钙镁铝层状双氢氧化物（Ca-Mg-Al LDH/GO）复合材料，并采用其在不同实验条件下去除 Eu(III) 和富里酸（FA）。此外，还获得了 Eu(III) 和 FA 的不同浓度梯度和不同添加顺序，揭示了不同的相互作用机制。实验结果表明，在三元体系中，FA 和 Eu(III) 的共存分别促进了 Eu(III)和 FA 的吸附性能。所获得的 Ca-Mg-Al LDH/GO 复合材料用于去除 Eu(III) 和 FA，进一步说明了其具有出色的化学物理稳定性和吸附能力，分别为 1.12×10-4mol/g 和 3.54×10-4mol/g。通过动力学过程和依赖温度的等温线证明了 Ca-Mg-Al LDH/GO 的显著吸附性能，表明动力学过程模拟采用拟二级模式，吸附等温线采用 Langmuir 模式进行了很好的模拟。XPS 谱分析表明，这些含氧基团在限制 Eu(III) 和 FA 吸附到 Ca-Mg-Al LDH/GO 复合材料表面方面发挥了重要作用。鉴于实验结果，Ca-Mg-Al LDH/GO 复合材料可用作有前景的吸附剂，可有效地回收再利用，用于从核燃料分离或核废水系统中去除 Eu(III) 和 FA。
