Uranium hexafluoride

Uranium hexafluoride is a compound used in the Uranium enrichment process. It forms solid grey crystals at STP, is highly toxic, reacts violently with water and is corrosive to most metals.

It is used in the uranium enrichment process because it has a triple point at 147C slightly higher than normal atmospheric pressure. This makes it very economical to process using the gaseous diffusion method. Isotopes of differ in their molecular weight based solely on the Uranium isotope present, as Fluorine has only a single stable naturally occurring isotope. By subjecting to repeated boiling and condensing, separation of U235 from U238 occurs by statistical enrichment. This process is very energy intensive.