SEM analyzes of powdered actinide compoundsImplementation in a hot laboratory

G. Jouan (1) , M. Virot (1) , E. Buravand (1)

1 CEA-DES (ex-DEN) - CEA-Direction des Energies (ex-Direction de l'Energie Nucléaire)

The fuel characterization laboratory in CEA Marcoule (LCC : “Laboratoire de Caractérisations des Combustibles”) works on radioactive solid characterization and especially on minor actinide powders (U, Pu, Am, Cm, ...). The powder disadvantage is to generate an important contamination inside the glove boxes and the equipment used for their characterization. The present communication is dedicated to a nuclearized FEG-SEM Zeiss Supra 55. This device is equipped with EDS and WDS combined detectors. The SEM is connected to a glove box on its sample introduction chamber with a flexible bellow in order to minimize ventilation vibrations. This type of nuclearization allows the SEM to be uncoupled from its glove box and highly simplifies its maintenance by avoiding contamination. In a first part, we will present the SEM nuclearization with curative maintenance examples (detector replacement and modifications). We will also discuss the feedback on EDS detector changes done in order to limit radiation impact. Induced effects by these changes will be discussed. In the second part, we will detail some results obtained with different detectors (SE2, BSE, InLens, EDS and WDS), and focus on analyzes performed in support of irradiated fuel reprocessing studies just after their dissolution. Zirconium molybdate precipitates are formed during the dissolution process causing significant fouling on the reprocessing process walls. The goal of this study realized in the high activity Laboratory Atalante is to control the precipitate growth in order to minimize their impact on the process. We will present some images and elemental analyzes performed on these samples, and what the nuclearized SEM enabled to highlight. A final section will demonstrate the interest of using a WDX detector in the case of radioactive samples, especially in the case of fission product separation (platinum group elements) or characteristic X-ray lines of actinides (Pu and Am for example).

Mots clés: SEM; actinide powders; WDS; EDS

Domaines: Physique Nucléaire Expérimentale [nucl-ex]; Physique Nucléaire Théorique [nucl-th]

G. Jouan, M. Virot, E. Buravand. SEM analyzes of powdered actinide compoundsImplementation in a hot laboratory. HOTLAB 2016, Oct 2016, Karlsruhe, Germany. ⟨cea-02438729⟩