Particle-chemical analysis of uranium and plutonium

Shinonaga, Taeko*; Donohue, D.*; Klose, D.*; Kuno, Takehiko* ; Kuno, Yusuke*; Esaka, Fumitaka  ; Esaka, Konomi; Magara, Masaaki  ; Sakurai, Satoshi ; Usuda, Shigekazu

More precise, accurate and prompt analyses of uranium and plutonium in various types of environmental samples are increasingly requested from the Clean Laboratory Unit, Safeguards Analytical Laboratory of IAEA in recent years. Particles show unique information and up to now, the secondary ion mass spectrometry (SIMS) has been employed for the uranium and plutonium particle analysis. The SIMS that is the most rapid method for particle analysis has, however, disadvantages for the analysis of the minor isotopes like U and U, i.e., not precise enough. The SIMS measurement also has a difficulty on Pu determination because of the interference of U-based isobaric signals. In this study, a combination of techniques, picking-up particles by a manipulator attached to a scanning electron microscope (SEM), followed by uranium and plutonium chemical purification and measurement by an inductively coupled plasma mass spectrometer (ICP-MS) and thermal ionization mass spectrometer (TIMS), was demonstrated for particle analysis using standard materials (NBS U500 and NBS 947) to develop a particle-chemical analysis.