PhD Defense | Gamze Çolak | Fabrication of Americium containing transmutation targets
Name: Gamze Çolak
February 27th, 2024
16h00 - 18h00
KU Leuven MTM (Materials Engineering) building Auditorium 00.13
Kasteelpark Arenberg 44
Fabrication of Americium containing transmutation targets
In the frame of sustainable development of nuclear energy, there is a need for a clear and proven vision on spent fuel management. After uranium and plutonium recycling, the long-term radiotoxicity of spent fuel is dominated by the minor actinides (MAs). In order to reduce the long-term radiotoxicity, the MAs could be separated and recycled via a partitioning and transmutation (P&T) strategy. In this PhD, porous uranium oxide (UOX) host matrix microspheres, allowing efficient infiltration of Am3+ (aq.) dopant solutions, were fabricated by the internal gelation process. As a novel application, starch was used as a low-temperature burnable pore-former. A stock solution of Am(NO3)3 (aq.) was first prepared by careful dissolution of AmO2 in nitric acid. Infiltration by Am3+ solution was performed on porous UOX microspheres which were originally fabricated outside of the shielded infrastructure. As a result, no secondary, MA-loaded liquid waste was generated during the process. Furthermore, the use of microspheres avoided the handling of powders, which decreased the risk for local contaminations during processing. A comprehensive microstructural characterization was conducted. The results revealed that a single-phase (U,Am)O2 composition with average Am3+ levels up to 30 mol% was obtained, with a homogenous distribution of metal cations. For the first time at SCK CEN, (U,Am)O2 transmutation targets have been fabricated and characterized. The methods developed in this work were specifically adopted to the limitations imposed by working in shielded infrastructure for the handling of highly-radioactive materials. They were found to be safe and very effective in obtaining the desired end-product at a laboratory scale application.
- Jozef Vleugels (KU Leuven)
SCK CEN mentors:
- Gregory Leinders
- Rémi Delville
Click here for a list of obtained PhD degrees.