uranium enrichment

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July 16, 2026

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Uranium enrichment is the process of increasing the concentration of the fissile isotope uranium-235 (U-235) in uranium. Natural uranium contains only about 0.72% U-235, with the remainder being mostly uranium-238 (U-238).12

Two primary methods are used for enrichment:
* Gaseous Diffusion: Uranium is converted into uranium hexafluoride (UF₆) gas. This gas is passed through porous barriers. Since U-235 molecules are lighter, they diffuse slightly faster, leading to a gradual increase in U-235 concentration after many repetitions.123
* Gas Centrifugation: UF₆ gas is spun at high speeds in centrifuges. The heavier U-238 isotopes accumulate along the walls, while the lighter U-235 isotopes concentrate near the center.13

Enriched uranium is crucial for nuclear reactors (low enrichment, 2-3% U-235) and nuclear weapons (high enrichment, 97-99% U-235).1

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Iran
Nuclear deal falters
…November 2020 its stockpile of enriched uranium had reached 12 times the level that had been permitted under the JCPOA. In January 2021 it began enriching uranium up to 20 percent purity; under the JCPOA it had been capped at 3.67 percent.
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…November 2020 its stockpile of enriched uranium had reached 12 times the level that had been permitted under the JCPOA. In January 2021 it began enriching uranium up to 20 percent purity; under the JCPOA it had been capped at 3.67 percent.
Read More