Uranberikelse

Uranberikelse is the process of increasing the concentration of the isotope uranium-235 (U-235) in uranium. Naturally occurring uranium is composed of about 99.3% uranium-238 (U-238) and only about 0.7% U-235. U-235 is the fissile isotope, meaning it can sustain a nuclear chain reaction, which is essential for both nuclear power generation and the creation of nuclear weapons.

The enrichment process is necessary because the natural concentration of U-235 is too low to be used directly in most nuclear reactors or for weapons. Nuclear reactors typically require uranium enriched to a concentration of 3% to 5% U-235, while nuclear weapons require much higher concentrations, often over 90% U-235.

Several methods are used for uranium enrichment, with gaseous diffusion and gas centrifuges being the most common. In gaseous diffusion, uranium hexafluoride gas is passed through porous membranes, with the lighter U-235 molecules passing through slightly faster than the heavier U-238 molecules. This process is repeated many times to achieve the desired enrichment level. Gas centrifuges use high-speed spinning machines to separate the isotopes based on their mass, with the U-235 isotopes being forced towards the outer wall of the centrifuge.

Uranium enrichment is a technologically complex and energy-intensive process. Due to its dual-use nature, it is subject to strict international controls and monitoring by organizations like the International Atomic Energy Agency (IAEA) to prevent the diversion of enriched uranium for non-peaceful purposes.