The potential of the eleven most sensitive emission wavelengths of americium (Am) for prospective isotopic and elemental analysis were investigated in detail using a commercial high resolution ICP-OES spectrometer. Calibration of the instrumental response was carried out through stepwise dilution of a 241Am stock solution (1 550 mg/kg) that was prepared in-house via chemical separation of the element from a concentrated plutonium (Pu) solution (115 g/L). Sector field ICP-MS, - and -spectrometry served to characterise extensively the employed Am and Pu solutions for their actual concentration, potential impurities and isotopic purity. Hyperfine splitting of relatively broad peaks (~10 pm) or multiplets, i.e. multiple peaks, were observed for most tested Am ICP-OES emission signals with 241Am and 243Am revealing identical signal patterns. The isotopic shift between 241Am and 243Am was generally small with a maximum difference of only ~3.7 pm found at =450.945 nm and =469.970 nm, respectively. As a consequence, the extraction of Am isotopic information from the ICP-emission spectra was limited. The use of a high efficiency sample introduction system helped to lower detection limits (LOD) for Am up to two orders of magnitude compared to previous values. While the emission wavelength =283.226 nm provided the lowest LOD of 0.07 µg/kg, distinct spectral interferences originating from thorium (Th) (=283.231 nm), would hamper the reliable determination of Am in Th-based nuclear fuels. A detailed interference study highlights the potential and drawback of each investigated emission wavelength for ICP-OES analysis of Am with special emphasis on nuclear fuel samples containing substantial amounts of Th, Pu and U.

KRACHLER Michael;  ALVAREZ SARANDES LAVANDERA Rafael;  CARBOL Paul;  MALMBECK Rikard;  VAN WINCKEL Stefaan; 

2013-06-27

ELSEVIER SCIENCE BV

JRC81924

0026-265X,   

https://publications.jrc.ec.europa.eu/repository/handle/JRC81924,   

10.1016/j.microc.2013.05.010,