Publikationen

Ultratrace Determination of Tc-99 in Small Natural Water Samples by Accelerator Mass Spectrometry with the Gas-Filled Analyzing Magnet System

Autor(en)
Francesca Quinto, Christoph Busser, Thomas Faestermann, Karin Hain, Dominik Koll, Gunther Korschinek, Stephanie Kraft, Peter Ludwig, Markus Plaschke, Thorsten Schäfer, Horst Geckeis
Abstrakt

In the frame of studies on the safe disposal of nuclear waste, there is a great interest for understanding the migration behavior of Tc-99. Tc-99 originating from nuclear energy production and global fallout shows environmental levels down to 10(7) atoms/g of soil (similar to 2 fg/g). Extremely low concentrations are also expected in groundwater after diffusion of Tc-99 through the bentonite constituting the technical barrier for nuclear waste disposal. The main limitation to the sensitivity of the mass spectrometric analysis of Tc-99 is the background of its stable isobar Ru-99. For ultratrace analysis, the Accelerator Mass Spectrometry (AMS) setup of the Technical University of Munich using a Gas-Filled Analyzing Magnet System (GAMS) and a 14 MV Tandem accelerator is greatly effective in suppressing this interference. In the present study, the GAMS setup is used for the analysis of Tc-99 in samples of the seawater reference material IAEA-443, a peat bog lake, and groundwater from an experiment of in situ diffusion through bentonite in the controlled zone of the Grimsel Test Site (GTS) within the Colloid Formation and Migration (CFM) project. With an adapted chemical preparation procedure, measurements of Tc-99 concentrations at the fg/g levels with a sensitivity down to 0.5 fg are accomplished in notably small natural water samples. The access to these low concentration levels allows for the long-term monitoring of in situ tracer tests over several years and for the determination of environmental levels of Tc-99 in small samples.

Organisation(en)
Isotopenphysik
Externe Organisation(en)
Karlsruher Institut für Technologie, Technische Universität München, Australian National University, TÜV SÜD Industrie Service GmbH, Friedrich-Schiller-Universität Jena
Journal
Analytical Chemistry
Band
91
Seiten
4585-4591
Anzahl der Seiten
7
ISSN
0003-2700
DOI
https://doi.org/10.1021/acs.analchem.8b05765
Publikationsdatum
04-2019
Peer-reviewed
Ja
ÖFOS 2012
103014 Kernphysik, 104026 Spektroskopie
Schlagwörter
Link zum Portal
https://ucris.univie.ac.at/portal/de/publications/ultratrace-determination-of-tc99-in-small-natural-water-samples-by-accelerator-mass-spectrometry-with-the-gasfilled-analyzing-magnet-system(59189691-e947-45a1-aed0-b2f596570db4).html