U.S. nuclear fuel recycling takes two steps forward

First, California-based Oklo announced plans to design, build, and operate a spent fuel recycling facility in Oak Ridge, Tenn. According to the company, the recycling facility will be part of a $1.68 billion advanced fuel center and will reprocess spent fuel into fresh fuel for fast reactors like Oklo’s Aurora Powerhouse, which the company plans to build at Idaho National Laboratory.

Second, Washington, D.C.-based Curio announced the completion of laboratory-scale demonstrations of its NuCycle voloxidation processing technology. The testing was done in collaboration with Idaho, Oak Ridge , Pacific Northwest , and Sandia National Laboratories with support from the Department of Energy’s ARPA-E CURIE program and GAIN voucher initiative.

Oklo expects to begin producing metal fuel for Aurora Powerhouses by the early 2030s, following regulatory review and approvals. Curio, meanwhile, is targeting a demonstration of its pilot-scale NuCycle modules by the fourth quarter of 2027.

Oklo details: According to Oklo, the recycling facility will recover usable fuel material from spent nuclear fuel and fabricate it into fuel for advanced reactors. The facility, which will reprocess spent fuel by electrorefining-based pyroprocessing, is the first phase of the company’s broader advanced fuel center, a multifacility campus aimed at supporting recycling and fuel fabrication.

Oklo has completed a licensing project plan for the recycling facility with the Nuclear Regulatory Commission and is currently in pre-application engagement with NRC staff. In July, Oklo successfully completed pre-application readiness assessment for Phase 1 of the combined license application for its first commercial Aurora Powerhouse.

The company also said it is also exploring opportunities with the Tennessee Valley Authority to recycle the utility’s spent fuel at the new facility and to evaluate potential power sales from future Oklo powerhouses in the region to TVA. According to Oklo, the collaboration would mark the first time a U.S. utility has explored recycling its used fuel using modern electrochemical processes.

Curio details: According to Curio, NuCycle is the first nuclear fuel recycling technology designed from the ground up with safeguards and proliferation-hardening integrated into its process to be tested and validated at the lab scale.

At ORNL, Curio demonstrated its voloxidation techniques, which the company said offer unprecedented efficiency and scalability in decladding spent fuel. During testing, more than 99.75 percent of the fuel was released from its zircaloy cladding, according to Curio. Under the DOE’s GAIN voucher program, ORNL completed criticality safety assessments of Curio’s next-generation equipment designs with no safety constraints identified, the company added.

The pulverized product from the decladding process was then shipped to PNNL, which validated Curio’s fluorination circuit. The decontamination process yielded enrichment-ready uranium hexafluoride at some of the purest levels ever recorded from a single-stage process, according to the company. Working with PNNL, Curio said it scaled the chemical process from milligram-level experiments to 100 grams, proving both its viability and scalability.

INL, meanwhile, provided Curio data on its electrolysis process for recycling fuel, in which a molten-salt bath was used to separate actinides. By systematically varying temperature and concentration, researchers were able to study the fundamental redox chemistry that will enable co-extraction of plutonium with uranium and minor actinides in a proliferation-hardened manner, the company said.

Data from these lab-scale experiments are now informing Curio’s work with Sandia to develop a comprehensive safeguards and security model. This collaboration will conduct iterative material control and accounting analysis, using the experimental results to create a nuclear fuel recycling process that is safeguarded by design.

Curio intends to complete its lab-scale demonstration with actual spent nuclear fuel at INL and is actively exploring a first pilot with the DOE.

Quotables: “Fuel is the most important factor in bringing advanced nuclear energy to market,” said Jacob DeWitte, Oklo cofounder and CEO. “By recycling used fuel at scale, we are turning waste into gigawatts, reducing costs, and establishing a secure U.S. supply chain that will support the deployment of clean, reliable, and affordable power.”

Curio CEO Ed McGinnis noted, “We are moving at a pace the industry has never seen to deliver a fundamentally new, safeguarded-by-design platform that will redefine the economics and security of the entire nuclear fuel cycle. These unprecedented results demonstrate the strength of public–private collaboration in advancing sustainable nuclear solutions.”