Nuclear Science and Engineering Center, Japan Atomic Energy Agency (JAEA), 2-4 Shirakata, Naka-gun, Ibaraki, 319-1195, Japan.
National Metrology Institute of Japan (NMIJ), National Institute of Advanced Industrial Science and Technology (AIST), 1-1-1 Umezono, Tsukuba, Ibaraki, 305-8563, Japan.
Anal Bioanal Chem. 2019 Feb;411(5):973-983. doi: 10.1007/s00216-018-1527-3. Epub 2018 Dec 14.
Determination of radiopalladium Pd is required to ensure radiation safety of the Pd extracted from spent nuclear fuel for recycling or disposal. We employed nanosecond laser ablation inductively coupled plasma quadrupole mass spectrometry (ns-LA-ICP-QMS) to simplify the analytical procedure of Pd. Pd was separated through a selective Pd precipitation reaction induced by pulsed laser irradiation that reduces Pd(II) ions to metal Pd(0). Laser ablation facilitates direct measurement of the Pd precipitates, skipping the dissolution and dilution procedure with aqua regia and HCl, which causes serious corrosion damage to the introduction system of the ICP. In the present study, Pd in natural Pd standard solution was used as an internal standard owing to its absence in spent nuclear fuel. Pd precipitates with diameters ranging from 0.2 to 0.5 μm, obtained by pulsed laser irradiation, were embedded uniformly on the surface of the centrifugal filter to form a microscopically thin and flat Pd surface. The resulting homogeneous Pd layer is suitable for obtaining a stable signal ratio of Pd/Pd (< 4%, 2RSD). The mass bias-corrected ratio of Pd/Pd and the amount of Pd were 0.163 ± 0.004 and 17.8 ± 0.6 ng, respectively, which correspond to the values obtained by solution nebulization measurement after the dissolution of identical Pd precipitates. Graphical abstract ᅟ.
为了确保从乏核燃料中提取的钯用于再循环或处置的辐射安全性，需要测定放射性钯（Pd）。我们采用纳秒激光烧蚀电感耦合等离子体质谱法（ns-LA-ICP-QMS）简化 Pd 的分析程序。通过脉冲激光辐照诱导的选择性 Pd 沉淀反应将 Pd(II)离子还原为金属 Pd(0)，从而实现 Pd 的分离。激光烧蚀便于直接测量 Pd 沉淀物，避免了使用王水和 HCl 的溶解和稀释程序，这会对 ICP 的引入系统造成严重的腐蚀损坏。在本研究中，由于乏核燃料中不存在 Pd，因此使用天然 Pd 标准溶液中的 Pd 作为内标。通过脉冲激光辐照获得的直径为 0.2 至 0.5 μm 的 Pd 沉淀物均匀嵌入在离心过滤器的表面上，形成微观上薄而平整的 Pd 表面。所得均匀的 Pd 层适合获得稳定的 Pd/Pd 信号比（<4%，2RSD）。经质量偏差校正后的 Pd/Pd 比值和 Pd 量分别为 0.163 ± 0.004 和 17.8 ± 0.6 ng，这与溶解相同 Pd 沉淀物后通过溶液雾化测量获得的值相对应。
