PhD Studentship: EPSRC - The Fate of Zeolites During Long Term Storage within Nuclear Fuel Ponds

The University of Manchester

Qualification Type:PhDLocation:ManchesterFunding for:UK StudentsFunding amount:£20,780 annual tax-free stipend set at the UKRI rate(for 2025/26) subject to annual uplift and tuition fees will be paid.Hours:Full TimePlaced On:3rd February 2026Closes:2nd March 2026

Application deadline: 02/03/2026

Research theme: Applied Environmental Chemistry

UK only

This 3.5-year PhD studentship is open to Home (UK) applicants. The successful candidate will receive an annual tax-free stipend set at the UKRI rate (£20,780 for 2025/26; subject to annual uplift), and tuition fees will be paid. We expect the stipend to increase each year.

The start date is October 2026.

We recommend that you apply early as the advert may be removed before the deadline.

Fuel ponds have been used for decades to store spent nuclear fuel. The management of these facilities is key to their safety and long-term decommissioning. During fuel storage pond operations zeolites (AW-500 Chabazite) have been commonly utilised to reduce the level of fission product radioactivity (e.g. 137Cs and 90Sr) within the ponds water, via various mechanisms (e.g. ion-exchange columns). At some sites (e.g. Sellafield, UK) container loaded with zeolites were immersed in the ponds, and subsequently sealed then stored within the fuel storage ponds for up to 30 years. During this time the zeolites and solution within the sealed containers have remained isolated from the pond waters, and a range of radiological, physical and chemical processes are likely to have led to significant changes in the physical, structural and chemical properties of the zeolite minerals over this period.

For example, the high doses of both beta and gamma radiation may have led to the production of defects and disorder within the zeolite structure, which can change its physical properties. This in turn could alter the ability of the zeolite to exchange key radionuclides, which may lead to release or enhanced adsorption of 90Sr and 137Cs. Understanding the likely changes in both the solid and solution phases during this zeolite aging process are key for the successful decommission of the zeolites in the ponds, as currently the properties of the materials sealed within are unknown, and won’t be fully revealed until the skips are opened and observed, a challenging task due to the extreme radioactive environment.

The aim of this project is to use experimental and modelling approaches to develop a detailed understanding of the physical, structural and chemical properties of zeolites, and associated fluids, stored for 30+ years in sealed containers within Sellafield nuclear fuel storage ponds. The experimental component will focus on materials characterisation and radionuclide partitioning using specialised experimental facilities within the NNUF RADER facility (https://www.nnuf.ac.uk/rader). This will include the use of state-of-the-art facilities approaches including beta/gamma irradiation (Dalton Cumbria Facility, DCF) and advanced electron/X-ray microscopy (e.g., Diamond synchrotron https://www.diamond.ac.uk). These studies will be combined with computational approaches to develop geochemical models (e.g. PHREEQC) to provide insight into the key processes controlling fluid and solid phase changes during the long-term aging .

The results of this study will provide detailed information on the physical and chemical properties of the zeolites which will help deliver the decommissioning for these components within Sellafield nuclear fuel ponds, a significant priority on site.

Applicants should have, or expect to achieve, at least a 2.1 honours degree or a master’s (or international equivalent) in a relevant science or engineering related discipline.

To apply, please contact the main supervisor, Prof Shaw - sam.shaw@manchester.ac.uk. Please include details of your current level of study, academic background and any relevant experience and include a paragraph about your motivation to study this PhD project.