Behavior of long-lived fission and activation products in the near-field of a repository for nuclear waste and possibilities of their retention (VESPA II)
- Karlsruhe Institute for Technology, Institute for Nuclear Waste Disposal (KIT-INE, Karlsruhe, Germany)
- Gesellschaft für Anlagen- und Reaktorsicherheit (GRS) GmbH (Braunschweig, Germany)
- Institut für Energie- und Klimaforschung Nukleare Entsorgung und Reaktorsicherheit (IEK-6, Jülich, Germany)
Long-term safety assessments for final disposals of high-level radioactive waste have to consider the release of radionuclides from the waste and their potential retention by the multi-barrier system. To date, it has been assumed in long-term safety analysis that there is only retention for cationic but not for anionic species within the near-field of final disposals.
In this context, the joint research project VESPA II, has the primary objective to investigate the retention of 79Se, 129I and 99Tc. In aquatic solutions, these elements mainly occur in anionic form and do not form poorly soluble phases. The goals of VESPA II are:
- filling the gaps on the reported thermodynamic data related to fission products and
- analyzing their retention by minerals phases likely found in the near-field repository, such as corrosion products.
HZDR is involved in the following work packages
- studying the surface speciation and incorporation of Tc(VII) and Tc(IV) on iron corrosion phases, environmental ubiquitous minerals and on LDH phases under reducing conditions and
- investigating the Tc chemistry and thermodynamics, especially for low oxidation states.
Bachelor/Master thesis topic
Analysis of technetium immobilization and its molecular retention mechanisms by Fe(II)-Al(III)-Cl layered double hydroxide.
Chemical Engineering Journal 408(2021), 127265
Technetium retention by gamma alumina nanoparticles and the effect of sorbed Fe²⁺
Journal of Hazardous Materials 833(2020), 122066
New insights into 99Tc(VII) removal by pyrite: A spectroscopic approach
Environmental Science & Technology 54(2020)5, 2678-2687
⁹⁹Tc immobilization by aluminum solids containing Fe(II) moieties
The 43th symposium on scientific basis for nuclear waste management, 21.-24.10.2019, Viena, Austria
Spectroelectrochemical studies of the Tc(VII) reduction in aqueous electrolyte media
Rodriguez, D.; Mayordomo, N.; Brendler, V.; Müller, K.; Stumpf, T.
17th international conference on the chemistry and migration behavior of actinides and fission products in the geosphere, 15.-21.09.2019, Kyoto, Japan
Reductive immobilization of 99Tc(VII) by different crystalline phases of iron sulfide (FeS2)
Rodriguez, D.; Mayordomo, N.; Brendler, V.; Müller, K.; Schild, D.; Stumpf, T.
Migration 2019 - 17th International Conference on the Chemistry and Migration Behavior of Actinides and Fission Products in the Geosphere, 15.-21.09.2019, Kyoto, Japan
Tage der Standortauswahl, 11.-12.02.2021, Freiberg, Deutschland
99Tc retention on pyrite and alumina: the effect of Fe2+
Rodríguez, D.; Mayordomo, N.; Stumpf, T.; Mueller, K.
The 10th International Symposium on Technetium and Rhenium – Science and Utilization, 03.-06.10.2018, Moscow, Russia