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How can thorium-232 be converted into fissionable uranium-233?
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actinoid element
Modern version of the periodic table of the elements (printable).
Thorium-232 is considered a fertile material, meaning it can be transformed into the fissile isotope uranium-233 through a process known as neutron capture within a nuclear reactor.12
The conversion process occurs in the following steps:
- Neutron Capture: When a nucleus of thorium-232 absorbs a slow-moving neutron, it is transformed into the isotope thorium-233.32
- Radioactive Decay: Thorium-233 is unstable and has a half-life of approximately 21.83 minutes. It undergoes radioactive decay through electron emission to become protactinium-233.2
- Final Transformation: Protactinium-233, which has a half-life of about 26.967 days, subsequently decays through electron emission to yield the fissile uranium-233.2
Once formed, this uranium-233 can be utilized as fuel for nuclear energy, either immediately or after being recovered from the irradiated reactor fuel through chemical processes such as the Thorex process.1