TEHRAN, Iran, AP -Iran’s nuclear chief said Wednesday his country has enriched uranium near the level needed to fuel reactors.
Nuclear chief Gholamreza Aghazadeh said Iran had enriched uranium to 4.8 percent purity, which surpasses the 3.6 percent level Tehran declared it had achieved last month. To produce electricity, nuclear reactors require uranium enriched to 5 percent.
Enrichment is a highly difficult process that takes gas produced from raw uranium and aims to increase its proportion of the uranium-235 isotope, needed for nuclear fission.
The gas is pumped into a centrifuge, which spins, causing a small portion of the heavier, more prevalent uranium-238 isotope to drop away. The gas then proceeds to other centrifuges — thousands of them — where the process is repeated, increasing the proportion of uranium-235.
Enrichment typically starts out with a gas that is 0.7 percent uranium-235. It must be boosted to around 5 percent to produce fuel for a reactor — or 90 percent for the material for a warhead.