Tc(Ⅶ)与Re(Ⅶ)在TEVA及AG1-X4树脂上的化学行为相似性

Chemical Behavioral Similarity of Tc(Ⅶ) and Re(Ⅶ) on TEVA and AG1-X4 Resins

样品中99Tc的测定需经过预处理及化学分离纯化等过程,由于流程复杂,往往存在锝的损失,因此选择合适的示踪剂是准确测定锝含量的关键。本工作采用静态法与柱实验相结合,分别研究了固相萃取树脂TEVA及离子交换树脂AG1-X4对样品中99Tc的分离纯化条件,探究了Re和Tc在化学分离纯化过程中的行为相似性。结果表明:TEVA及AG1-X4树脂对ReO-4和TcO-4都有着较强的吸附能力,选择pH为9~11范围上柱,采用高浓度HNO3洗脱,Re和Tc的化学行为基本一致,且回收率均在90%以上。通过控制实验条件,可利用Re作为Tc的稳定非同位素化学类似物获取99Tc在分析流程中的化学回收率。

The measurement of 99Tc in the sample needs to go through pretreatment, separation, and purification processes, which inevitably cause losses of technetium. Therefore, selecting the appropriate tracer is the key to accurately determine the content of technetium. This work adopted the static method combined with column experiment to investigate the separation and purification conditions of 99Tc on extraction chromatographic resin(TEVA) and ion exchange resin(AG1-X4), and to explore the behavioral similarities of Re and Tc during chemical separation and purification processes. The results show that TEVA and AG1-X4 resins have strong load capacity for ReO-4 and TcO-4, the loading condition is in the pH range of 9-11, then the target elements can be eluted with high concentration of HNO3. The chemical behaviors of Re and Tc are basically the same, and the recovery are all above 90%. Re can be used as a stable non-isotopic chemical analogue of Tc to estimate the recovery yield of 99Tc in the analytical process by controlling the experimental parameters.