Experimental Actinide Nano-chemistry for the Future of the Civil UK Plutonium Inventory
Supervisor: Dr Emma Gibson
Industry Partner:
- Sellafield
- UK National Nuclear Laboratory
- Nuclear Decommissioning Authority
School: Chemistry
Description:
After six decades of commercial nuclear fuel reprocessing at Sellafield, the UK has the largest inventory of separated civilian Pu worldwide. This inventory is in the form of actinide oxide powders (AnO2 where An = U, Pu; or mixtures of An = MOx). The AnO2 are chemically reactive towards atmospheric gases and the products of water and air radiolysis, resulting in the production and consumption of reactive gas mixtures, and therefore changes to material properties over time.
The UofG team work with UK civil nuclear industry partners and use a combination of synthetic actinide chemistry and heterogeneous catalysis to deliver the experimental data urgently needed to support the current and future management of the UK’s civil plutonium.
Surrogate materials for Pu are actinide oxide nanoparticles (AnO2-NP, An = U, Th). These will be synthesised by wet chemistry and thermal decomposition from molecular precursors following the industrial route. Gaseous products will be monitored by an in-line mass spectrometer and the AnO2-NP characterised by standard techniques (BET, PXRD, XRF, ATR-IR, Raman).
Furthermore, this project focuses on development of methodology and parameters (humidity, carrier gas, temperature) for running in-situ Diffuse Reflectance Infrared Fourier Transform Spectroscopy (DRIFTS) experiments with active materials and specifically probing the interaction of water with AnO2-NP. Studying aged Pu using DRIFTS is a current focus of the Pu scientists at UK NNL, in collaboration with US LANL. Experimental work has been carefully designed in collaboration (ARC proposal) to generate data directly comparable to ongoing work. UofG working with surrogate materials in a university lab, can test more variables much more quickly, more easily handle gases and therefore can develop in-situ measurements with unique capability to study mechanism. Therefore, delivering the data to bridge the knowledge gap between model and real systems, and to draw out the physical constants needed to establish the structure-property relationships.