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US 4,247,522 AGranted
Method of purifying uranium tetrafluoride hydrate and preparing uranium (VI) peroxide hydrate using a fluoride precipitating agent
AssigneeGardinier, Inc.
InventorsRonald L. Pyman, JoAnne LeFever
Life of this patent
Estimating the term…
Abstract
A method of preparing uranium (VI) peroxide hydrate from uranium tetrafluoride hydrate, comprising the steps of digesting uranium tetrafluoride hydrate in an aqueous acid in the presence of a fluoride precipitating agent to produce an aqueous uranium solution, filtering the aqueous uranium solution to remove precipitated fluorides and undissolved material, adjusting the aqueous uranium solution to a pH between about 1 to about 3, reacting the aqueous uranium solution with peroxide to precipitate uranium (VI) peroxide hydrate, and separating the precipitated uranium (VI) peroxide hydrate.
Claims24
A method of preparing uranium (VI) peroxide hydrate from uranium tetrafluoride hydrate, comprising the steps of:
- (a) digesting uranium tetrafluoride hydrate in an aqueous acid in the presence of a fluoride precipitating agent to precipitate fluoride ions and produce an aqueous uranium solution,
- (b) filtering the aqueous uranium solution of step (a) to remove precipitated fluorides and undissolved material,
- (c) adjusting the aqueous uranium solution of step (b) to a pH between 1 and 3,
- (d) reacting the aqueous uranium solution of step (c) with peroxide to precipitate uranium (VI) peroxide hydrate,
- (e) separating the precipitated uranium (VI) peroxide hydrate of step (d),
- (f) digesting the uranium (VI) peroxide hydrate of step (e) in an aqueous acid in the presence of a fluoride complexing agent to produce an aqueous uranium solution,
- (g) adjusting the aqueous uranium solution of step (f) to a pH between about 1 to about 3,
- (h) reacting the aqueous uranium solution of step (g) with peroxide to precipitate uranium (VI) peroxide hydrate, and
- (i) separating the precipitated uranium (VI) peroxide hydrate of step (h).
6 more elements
A method of preparing uranium (VI) peroxide hydrate from uranium tetrafluoride hydrate, comprising the steps of:
- (a) digesting uranium tetrafluoride hydrate in an aqueous acid in the presence of a fluoride precipitating agent to precipitate fluoride ions and produce an aqueous uranium solution,
- (b) filtering the aqueous uranium solution of step (a) to remove precipitated fluorides and undissolved material,
- (c) adjusting the aqueous uranium solution of step (b) to a pH between about 1 to about 3,
- (d) reacting the aqueous uranium solution of step (c) with peroxide to precipitate uranium (VI) peroxide hydrate, and
- (e) separating the precipitated uranium (VI) peroxide hydrate of step (d).
2 more elements
A method of purifying uranium (VI) peroxide hydrate, comprising the steps of:
- (a) digesting uranium (VI) peroxide hydrate concentrate in an aqueous acid in the presence of a fluoride complexing agent to produce an aqueous uranium solution,
- (b) adjusting the aqueous uranium solution of step (a) to a pH between about 1 to about 3,
- (c) reacting the aqueous uranium solution of step (b) with peroxide to precipitate uranium (VI) peroxide hydrate, and
- (d) separating the precipitated uranium (VI) peroxide hydrate of step (c).
1 more element
A method of preparing uranium (VI) peroxide hydrate from uranium tetrafluoride hydrate, comprising the steps of:
- (a) digesting an impure uranium-containing compound in nitric acid in the presence of a fluoride precipitating agent to precipitate fluoride ions and produce an aqueous uranium solution, wherein said uranium-containing compound consists essentially of uranium tetrafluoride hydrate;
- (b) filtering the aqueous uranium solution of step (a) to remove precipitated fluorides and undissolved material;
- (c) adjusting the aqueous uranium solution of step (b) to a pH between 1 and 3;
- (d) reacting the aqueous uranium solution of step (c) with peroxide to precipitate uranium (VI) peroxide hydrate;
- (e) separating the precipitated uranium (VI) peroxide hydrate of step (d);
- (f) digesting the uranium (VI) peroxide hydrate of step (e) in nitric acid in the presence of a fluoride complexing agent to produce an aqueous uranium solution;
- (g) adjusting the aqueous uranium solution of step (f) to a pH between about 1 to about 3;
- (h) reacting the aqueous uranium solution of step (g) with peroxide to precipitate uranium (VI) peroxide hydrate, and
- (i) separating the precipitated uranium (VI) peroxide hydrate of step (h), whereby a purified uranium (VI) peroxide hydrate containing no more than 0.15% fluoride based on the weight of uranium is produced.
6 more elements
A method of preparing uranium (VI) peroxide hydrate from uranium tetrafluoride hydrate, comprising the steps of:
- (a) mixing uranium tetrafluoride hydrate with a calcium compound slurry;
- (b) adding to the mixture of step (a) nitric acid, whereby an aqueous uranium solution is produced and a calcium flouride precipitate is formed;
- (c) adding a stoichiometric amount of sulfuric acid to the mixture of step (b) to precipitate excess calcium cations as calcium sulfate;
- (d) filtering the aqueous uranium solution of step (c) to remove precipitates and undissolved material;
- (e) adjusting the aqueous uranium solution of step (d) to a pH between about 1 to about 3,
- (f) reacting the aqueous uranium solution of step (e) with peroxide to precipitate uranium (VI) peroxide hydrate, and
- (g) separating the precipitated uranium (VI) peroxide hydrate of step (f).
4 more elements
A method of preparing a purified uranium (VI) peroxide hydrate from phosphate rock, said method comprising the steps of:
- (a) treating phosphate rock with sulfuric acid, whereby calcium sulfate is precipitated and phosphoric acid containing dissolved uranium is released;
- (b) extracting uranium from said phosphoric acid with a solvent which is immiscible with water and which has a high affinity for uranium;
- (c) separating the uranium-laden solvent of step (b) from said phosphoric acid;
- (d) contacting said uranium-laden solvent of step (c) with hydrofluoric acid to precipitate the uranium in the form of impure uranium tetrafluoride hydrate;
- (e) digesting said impure uranium tetrafluoride hydrate of step (d) in nitric acid in the presence of a fluoride precipitating agent to precipitate fluoride ions and produce an aqueous uranium solution;
- (f) filtering the aqueous uranium solution of step (e) to remove precipitated fluorides and undissolved material;
- (g) adjusting the aqueous uranium solution of step (f) to a pH between 1 and 3;
- (h) reacting the aqueous uranium solution of step (g) with peroxide to precipitate uranium (VI) peroxide hydrate;
- (i) separating the precipitated uranium (VI) peroxide hydrate of step (h);
- (j) digesting the uranium (VI) peroxide hydrate of step (i) in nitric acid in the presence of a fluoride complexing agent to produce an aqueous uranium solution;
- (k) adjusting the aqueous uranium solution of step (j) to a pH between about 1 to about 3;
- (l) reacting the aqueous uranium solution of step (k) with peroxide to precipitate uranium (VI) peroxide hydrate;
- and
- (m) separating the precipitated uranium (VI) peroxide hydrate of step (l), whereby a purified uranium (VI) peroxide hydrate containing no more than 0.15% fluoride based on the weight of uranium is produced.
11 more elements
Dependencies are inferred from the claim text.