Department of Chemistry, Isfahan University of Technology, Isfahan, 84156-83111, Iran.
Department of Chemistry, University of Isfahan, Isfahan, 81744-73441, Iran.
Talanta. 2021 Jan 15;222:121509. doi: 10.1016/j.talanta.2020.121509. Epub 2020 Aug 11.
A simple analytical procedure has been developed for the determination of trace rare earth elements (REEs) in uranium materials by inductively coupled plasma mass spectrometry (ICP-MS) and inductively coupled plasma optical emission spectrometry (ICP-OES), after selective extraction of uranium matrix using tri(2-ethylhexyl)phosphate (TEHP). The separation method reduces uranium concentration in the raffinate to less than 10 mg L (from initial value of ~40,000 mg L), thus, eliminating severe matrix interferences from uranium, such as isobaric and polyatomic interferences in ICP-MS, and spectral interferences in ICP-OES. The raffinate is directly used for the analysis of REEs, without any pretreatment. The proposed method was validated by applying it to the ICP-MS determination of REEs in uranium dioxide (UO) samples, by spiking with standard reference REE solutions and performing the recovery tests. The recoveries ranged from 94.0 to 105.5%. The validation was also performed similarly for ICP-OES measurements on UO as well as UO samples, which provided recoveries in the ranges of 96-105.8% and 99.2-101.6%, respectively. The method offers a fast, simple and effective method with low detection limit, and is suggested for the determination of REEs in uranium-based nuclear grade materials such as uranyl nitrate hexahydrate, uranium hexafluoride and uranium trioxide.
已开发出一种简单的分析程序，用于通过电感耦合等离子体质谱（ICP-MS）和电感耦合等离子体发射光谱（ICP-OES）测定铀材料中的痕量稀土元素（REEs），方法是使用磷酸三（2-乙基己基）酯（TEHP）选择性萃取铀基体。该分离方法将萃余物中的铀浓度降低至 10 mg/L 以下（从初始值约 40000 mg/L 降低），从而消除了铀的严重基质干扰，例如 ICP-MS 中的同量异位素和多原子干扰，以及 ICP-OES 中的光谱干扰。无需任何预处理，即可直接使用萃余物分析 REEs。该方法通过用标准参考 REE 溶液进行标准加入和回收测试，应用于二氧化铀（UO）样品中 REEs 的 ICP-MS 测定，验证了该方法的准确性。回收率在 94.0%至 105.5%之间。同样对 UO 以及 UO 样品进行了 ICP-OES 测量的验证，回收率分别在 96-105.8%和 99.2-101.6%范围内。该方法提供了一种快速、简单、有效的方法，具有较低的检测限，建议用于测定硝酸六水合铀、六氟化铀和三氧化铀等铀基核级材料中的 REEs。
