Patent · US Expired

Production of uranium dioxide

US4053559A · kind A · utility

14Cited by
7References
8Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJun 14, 1976
Grant dateOct 11, 1977
Priority date
Expiry dateJun 14, 1996

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY02P20/129
  • WIPO fieldMaterials, metallurgy
  • WIPO sectorChemistry

Abstract

A continuous, four stage fluidized bed process for converting uranium hexafluoride (UF.sub.6) to ceramic-grade uranium dioxide (UO.sub.2) powder suitable for use in the manufacture of fuel pellets for nuclear reactors is disclosed. The process comprises the steps of first reacting UF.sub.6 with steam in a first fluidized bed, preferably at about 550.degree. C, to form solid intermediate reaction products UO.sub.2 F.sub.2, U.sub.3 O.sub.8 and an off-gas including hydrogen fluoride (HF). The solid intermediate reaction products are conveyed to a second fluidized bed reactor at which the mol fraction of HF is controlled at low levels in order to prevent the formation of uranium tetrafluoride (UF.sub.4). The first intermediate reaction products are reacted in the second fluidized bed with steam and hydrogen at a temperature of about 630.degree. C. The second intermediate reaction product including uranium dioxide (UO.sub.2) is conveyed to a third fluidized bed reactor and reacted with additional steam and hydrogen at a temperature of about 650.degree. C producing a reaction product consisting essentially of uranium dioxide having an oxygen-uranium ratio of about 2 and a low residual fl…

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.