Uranhexafluorid

BeschreibungUranium hexafluoride has a molecular formula of UF6. It is a colorless, volatile crystal that sublimes and reacts vigorously with water. It is highly corrosive and is a radiation risk. The four-digit UN identification number for fissile material containing more than 1% of uranium 235 is 2977; for lower specific activity, the number is 2978. Uranium hexafluoride is used in a gaseous diffusion process for separating isotopes of uranium.

VerwendenUranium hexafluoride is used in uranium processing because its unique properties make it very convenient. It can conveniently be used as a gas for processing, as a liquid for filling or emptying containers or equipment, and as a solid for storage, all at temperatures and pressures commonly used in industrial processes.

synthetischeThere are many ways of making UF6. Although reaction of uranium and fluorine was first noted by Henri Moissan, first isolator of fluorine, c.1900, UF6 was originally reported by Ruff (pioneer of syntheses of many metal fluorides) and Heinzelmann in 1911. They made it by fluorination of uranium, and also by fluorination of UC2; fluorine needs to be heated to react with uranium, unless it is finely divided. U (s) + 3 F2 (g)---> UF6 (g) UC2 (s) + 7 F2 (g) ---> UF6 (g) + 2 CF4 (g) (at 350°C) An unusual reaction which does not use fluorine (but which has not been employed commercially) is:- 2 UF4 (g) + O2 (g)---> UF6 (g) + UO2F2 (g) The main process used industrially employs fluorination of UF4 at around 500°C. It is a very exothermic process; temperatures can reach 1100°C in reactors with capacities of up to 380 kg per hour. UF4 (g) + F2 (g)---> UF6 (g)