Due to its high solubility, radioactivity and toxicity, the separation of selenium from spent fuel reprocessing waste and industrial wastewater has attracted much attention. In this study, a novel adsorbent FeOOH@SiO₂ with particle size of ∼100 μm was successfully prepared by loading FeOOH on micron-sized silica with emulsion methods. FeOOH@SiO₂ with good acid resistance, γ-irradiation and thermal stability exhibits excellent adsorption abilities for Se(IV) and Se(VI) including fast adsorption kinetics, great adsorption capacities (11.0 mg/g for Se(IV) and 6.04 mg/g for Se(VI)) and preferable adsorption selectivity. It is worth noting that FeOOH@SiO₂ can still remove nearly 90 % of Se(IV) and 80 % of Se(VI) even in 3 mol/L HNO₃ system. Combined with the observations from X-ray photoelectron spectroscopic characterization and surface potential measurement, the adsorption mechanism caused with electrostatic attraction and the formation of inner complexes for Se(IV), and reduction reaction and partial formation of outer complexes for Se(VI) can be deduced. After 4 adsorption–desorption cycles, FeOOH@SiO₂ still exhibits satisfactory reusability. Dynamic column experiments also demonstrated that FeOOH@SiO₂ exhibited excellent removal capabilities towards Se(IV) and Se(VI) from real water samples. The present work demonstrates that FeOOH@SiO₂ has great potential application for ⁷⁹Se removal in highly acidic nuclear waste.

由于硒的高溶解度、放射性和毒性，从乏燃料后处理废物和工业废水中分离硒备受关注。本研究通过乳液法将FeOOH负载在微米级二氧化硅上，成功制备了粒径为~100 μm的新型吸附剂FeOOH@SiO _{2 。}FeOOH@SiO ₂具有良好的耐酸性、γ-辐照和热稳定性，对 Se(IV) 和 Se(VI) 表现出优异的吸附能力，包括快速的吸附动力学、巨大的吸附容量（Se(IV) 为 11.0 mg/g 和 6.04 mg /g 对于 Se(VI)) 和优选的吸附选择性。值得注意的是，即使在 3 mol/L HNO _{3中，FeOOH@SiO 2仍然可以去除近 90 % 的 Se(IV) 和 80 % 的 Se(VI)}系统。结合 X 射线光电子能谱表征和表面电位测量的观察，Se(IV) 的静电引力和形成内部配合物的吸附机制，以及 Se(VI) 的还原反应和部分形成外部配合物的吸附机制可以被推导出来。经过 4 次吸附-解吸循环后，FeOOH@SiO ₂仍表现出令人满意的可重复使用性。动态色谱柱实验还表明，FeOOH@SiO ₂对真实水样中的 Se(IV) 和 Se(VI) 表现出优异的去除能力。目前的工作表明，FeOOH@SiO ₂在高酸性核废料中去除⁷⁹ Se具有巨大的潜在应用。