Abstract

The study describes direct precipitation, original template, and additional thermal reduction methods for the synthesis of materials based on cobalt oxides and their composites, promising as magnetic sorbents for the selective extraction and preconcentration of uranium(VI) from aqueous media. The thermal decomposition of intermediates and the phase formation of final materials were studied by differential thermal analysis and powder X-ray diffraction. The surface morphology and structure of the obtained sorbent samples were investigated. The sorption activity and capacity of the materials were estimated in relation to the extraction of uranyl ions from aqueous solutions over a broad pH range (2–10), in particular, in the presence of carbonate ions (0.001, 0.01, 0.1, and 1 mg/L). It was found that quantitative sorption of uranium(VI) is dictated, to a higher extent, by the composition of the sorbent solid phase containing metallic cobalt. A set of magnetic measurements were carried out and magnetic characteristics of sorption materials were determined. The saturation magnetization for reduced sorbents can reach 133–237 emu/g, which is an additional benefit for their separation from solutions after treatment by magnetic separation techniques.

中文翻译：

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氧化钴及其还原形式的磁性材料的合成与吸附特性

摘要

该研究描述了直接沉淀法，原始模板以及用于基于氧化钴及其复合材料的材料合成的其他热还原方法，有望作为磁性吸附剂，用于从水性介质中选择性萃取和预浓缩铀。通过差热分析和粉末X射线衍射研究了中间体的热分解和最终材料的相形成。研究了所得吸附剂样品的表面形态和结构。在宽的pH范围（2-10）中，特别是在存在碳酸根离子（0.001、0.01、0.1和1）的情况下，估计了与从水溶液中提取铀酰离子有关的材料的吸附活性和容量。毫克/升）。发现铀（VI）的定量吸附是必需的，更高的程度是由含金属钴的吸附剂固相组成。进行了一组磁性测量并确定了吸附材料的磁性。还原吸附剂的饱和磁化强度可以达到133–237 emu / g，这是通过磁分离技术处理后将它们从溶液中分离出来的另一个好处。