MRS – Scientific Basis for Nuclear Waste Management symposium 2015, Montpellier

The Institute of Crystallography (IfK) at RWTH Aachen University and the Institute of Energy and Climate Research (IEK) -6 of Forschungszentrum Jülich cooperate, inter alia, within the framework of the Federal Ministry of Education and Research (BMBF) funded joint project "Conditioning" (Fundamental studies for immobilizing long-lived radionuclides by incorporation into repository relevant ceramics). Our latest high profile joint activity was the participation in the symposium "Scientific Basis for Nuclear Waste Management" of the MRS (Materials Research Society) in Montpellier.

The meeting of the MRS is held in Boston annually (this year: 29.11.-04.12.2015), the Symposium on Nuclear Waste Management, however, is organized every second year by leading international research groups and is held at various locations, this year at the French Mediterranean Coast. Organized by the Université de Montpellier, the CEA Marcoule (Commissariat à l'énergie atomique et aux énergies alternatives), the CNRS (Centre national de la recherche scientifique), and the Forschungszentrum Jülich, the most recent scientific findings in the field of nuclear waste management were presented and discussed from 2nd to 6th November 2015.

The disposal of highly radioactive waste will remain a relevant topic for research in the Federal Republic of Germany in the long run. Currently, direct disposal of spent fuel is aimed at in this country. Nevertheless, it is important for specific waste streams (such as minor actinides) to provide alternative matrices for the immobilization of the radionuclides. Due to its flexibility to chemical replacement and its relative resistance to radiation (good recrystallization behavior), the monazite structure type appears to be a suitable ceramic matrix for the immobilization of minor actinides.

Natural monazite, with an age of up to 3.2 billion years, contains up to 27 weight-percent of UO2 and ThO2 (Lumpkin 2006), without exhibiting significant radiation damage. For these and other reasons, ceramic monazite phases are potential candidates for future waste management strategies. The aim of our joint research project within the framework of JARA-ENERGY is the development and characterization of new phases for the permanent incorporation of actinides.

The successful development of such immobilization phases represents a new option for safe nuclear waste disposal.

Figure 2: Single crystals of La(1-x)PrxPO4 from left to right: x = 0.2, 0.4, 0.6, 0.8 

Literature: Gregory R. Lumpkin, Ceramic Waste Forms for Actinides, Elements, Vol.  2, pp 365-372
MRS: www.mrs.org
Université de Montpellier: http://www.umontpellier.fr/
CEA Marcoule: http://portail.cea.fr/
CNRS: http://www.cnrs.fr/