Heidelberg 2015 – wissenschaftliches Programm
UP 13.13: Poster
Donnerstag, 26. März 2015, 10:45–19:45, G/Foyer
Development of a sample preparation procedure for the simultaneous determination of Np and Pu in clay samples — •Tobias Renz1, Francesca Quinto1, Markus Lagos1, Markus Plaschke1, Andreas Bauer1, Horst Geckeis1, and Heinrich Taubald2 — 1INE, KIT, Eggenstein-Leopoldshafen, Germany — 2Eberhard Karls Universität, Tübingen, Germany
Neptunium (Np) and plutonium (Pu) are two key radionuclides for the long-term disposal of nuclear waste. Within this context Opalinus Clay formations are considered as a potential location for disposal of high-level radioactive waste. In the framework of experiments studying the diffusion behavior and retention of actinides under repository conditions, the present work focuses on the development of an analytical-chemical procedure for the determination of Np and Pu in clay (or clay-rich soil) samples. The procedure aims at the simultaneous determination of Np and Pu at femto- to attogram levels with AMS. Fields of application are the investigation of global fallout actinides in environmental clay-rich samples or the diffusion behavior of actinides in compacted clay liners used as technical barriers in nuclear waste repositories. Clay samples are spiked with certified standards of Pu-242 and Np-237. The analytical method, including a) leaching of the spiked clay samples, b) redox adjustments of Np and Pu, c) chromatographic separation of Np and Pu from the sample matrix and d) measurement of the actinides with Sector Field (SF)-ICP-MS will be presented. The suitability of a Pu isotope as non-isotopic tracer for determination of Np-237 is evaluated by determing the chemical yield using SF-ICP-MS.