Uranium dioxide
The most widely used nuclear fuel worldwide. Sintered ceramic pellets (~1 cm × 1 cm) clad in zirconium alloy, assembled into rods and then fuel assemblies — this is what fissions in the core of PWR, BWR and EPR reactors.
Physical properties
Structure
Uses and applications
- Light-water reactor fuel (PWR, BWR — ~85 % of the global fleet)
- MOX fuel (UO₂ + PuO₂ blend) — recycling of plutonium from reprocessing
- Radioisotope sources for research and instrumentation
- High-purity nuclear ceramics
Safety (GHS)
Chemical toxicity (kidneys) and radioactivity (α emitter). Strictly controlled handling in the closed nuclear cycle. Fissile material subject to non-proliferation.
Constituent elements
References
Related processes
Industrial processes involving this compound.
- Nuclear energyInput
Pressurized Water Reactor (PWR)
The most widely deployed nuclear reactor design in the world (~70 % of the fleet). Primary-loop water, pressurized to 155 bar to stay liquid at 320 °C, carries fission heat from UO₂ fuel to a steam generator that feeds the turbine.
- Nuclear energyInput
Boiling Water Reactor (BWR)
Direct-cycle nuclear reactor: core water boils at 285 °C / 70 bar to produce the steam that drives the turbine directly, without a secondary loop. ~70 reactors in service (~25 % of the world fleet), mainly in the United States, Japan and Sweden.