Molten salt reactor (MSR) technologies are generating significant interest globally for a wide range of nuclear applications in both public and private sectors. While there is a primary focus on reactor technology at the international level, safety and licensing are also receiving some attention. The chemistry of the fuel cycle is recognized as playing a crucial role in the development and deployment of MSRs, as noted by both the NEA Expert Group on Fuel Recycling and Waste Technology (EGFRW) and the IAEA Technical Working Group on Nuclear Fuel Cycle Options and Spent Fuel Management (TWG-NFCO).
To address the challenges of chemical processes and technologies in MSR fuel cycles, the NEA and IAEA jointly organized an international workshop on the chemistry of fuel cycles for molten salt reactor technologies in Vienna, Austria, on 2-6 October 2023. The workshop brought together over 40 participants from 13 countries and the European Commission, including MSR developers, research and development (R&D) organizations, regulators, and industry experts.
The program of the workshop included several technical sessions on MSR concepts and nuclear fuel cycles, salt preparation, online and offline processing, and cross-cutting issues. Each session consisted of technical presentations, a “thoughts from the floor” session to address topics not covered by the presentations, and a panel discussion involving all the presenters. During the working sessions, participants were able to engage in further discussion and collaborate to identify gaps and R&D needs in areas such as experimental underpinning, irradiations, monitoring and operation, and irradiated fuel treatment (material and waste streams). Participants also discussed potential ways to address these issues and made recommendations for potential future activities.
The event confirmed the growing global interest in molten salt technologies and highlighted the added value that international cooperation can bring to the scientific community, MSR developers, and future user countries.