Preparation and sublimation of uranium tetrafluoride for the production of thin 235UF4 targets

Uranium tetrafluoride powder is used at the EC-JRC-IRMM for the production of thin uranium isotopic layers for nuclear physics experiments. The previously used dry chemical method to convert triuranium octoxide (U3O8) into uranium tetrafluoride (UF4) by means of hydrofluorination was replaced by a less hazardous wet chemical precipitation method. The triuranium octoxide was first converted into uranylchloride. In the next step the uranium(VI) was reduced to uranium(IV) by adding tin(II) chloride. Finally the reduced uranium(IV) chloride was converted into a fluoride with a hydrogen fluoride solution and a powder residue was formed that consisted of uranium tetrafluoride. The powder was then used for the production of thin layers of 235UF4 by sublimation from a resistance-heated Ta crucible. This paper describes in detail the different radiochemical steps of the wet chemical precipitation from U3O8 to UF4 and the sublimation of uranium tetrafluoride for the preparation of thin uniform layers by vapour deposition.

SIBBENS Goedele;  MOENS Andre;  EYKENS Roger; 

2015-05-12

SPRINGER

JRC91667

0236-5731,   

http://rd.springer.com/article/10.1007/s10967-015-4137-y,    https://publications.jrc.ec.europa.eu/repository/handle/JRC91667,   

10.1007/s10967-015-4137-y,