A study on artificial rare earth (RE2O3) based neutron absorber

Area of Science:

• Nuclear Engineering
• Materials Science
• Waste Management

Background:

• Spent nuclear fuel contains rare earth elements, byproducts of uranium fission.
• Pyroprocessing recovers uranium and transuranic elements, yielding High-Level Waste (HLW) rich in rare earth oxides (RE2O3).

Purpose of the Study:

• To evaluate artificial rare earth compounds (RE2O3) as neutron absorption materials for criticality control.
• To assess the feasibility of using HLW as a neutron absorber in spent fuel storage systems.

Main Methods:

• Analysis of artificial rare earth compound characteristics, including activity and neutron absorption cross-section.
• Comparison of neutron absorption capabilities with established materials like Boral™.

Main Results:

• The artificial rare earth compound exhibits enhanced neutron absorption probability across all energy ranges.
• The material demonstrates potential for maintaining sub-criticality for over 40 years, comparable to Boral™.

Conclusions:

• Artificial rare earth compounds derived from HLW are viable neutron absorbers for spent fuel criticality control.
• This approach offers an efficient dual-purpose solution for radioactive waste management and nuclear safety.