Patent US4234555A successfully refreshed from Google Patents.
US4234555A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Removal of uranium from aqueous HF solutions
Assignee: United States Department of Energy
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Filing: 1978-06-29
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Granted: 1980-11-18
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Expires: 1998-06-29
Abstract
Abstract This invention is a simple and effective method for removing uranium from aqueous HF solutions containing trace quantities of the same. The method comprises contacting the solution with particulate calcium fluoride to form uranium-bearing particulates, permitting the particulates to settle, and separting the solution from the settled particulates. The CaF2 is selected to have a nitrogen surface area in a selected range and is employed in an amount providing a calcium fluoride/uranium weight ratio in a selected range. As applied to dilute HF solutions containing 120 ppm uranium, the method removes at least 92% of the uranium, without introducing contaminants to the product solution.
Inventors
- 👤 Howard Pulley
- 👤 Steven F. Seltzer
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 19:04
CPC Classifications
C; C01; C01B; C01B7/00; C01B7/19; C01B7/191; C01B7/195; C01B7/197; G; G21; G21F; G21F9/00; G21F9/04; G21F9/06; G21F9/12
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
57 words
The method of decreasing the uranium content of an aqueous HF solution containing uranium to provide a product aqueous HF solution of increased purity, said method comprising: mixing particulate calcium fluoride with said solution to form uranium-bearing particulates, permitting said particulates to sediment from said solution, and separating the resulting aqueous HF solution from the settled particulates.
Claim 2
Independent Claim
57 words
The method of decreasing the uranium content of an aqueous HF solution containing uranium to provide a product aqueous HF solution of increased purity, said method comprising: mixing particulate calcium fluoride with said solution to form uranium-bearing particulates, permitting said particulates to sediment from said solution, and separating the resulting aqueous HF solution from the settled particulates.
Claim 3
Dependent Claim
32 words
The method of claim 1 wherein said calcium fluoride is mixed with said solution in an amount providing a calcium fluoride-to-uranium weight ratio in the range of from about 8 to 75.
Claim 4
Dependent Claim
26 words
The method of claim 1 wherein said calcium fluoride has a nitrogen surface area in the range of from about 1 to 200 m 2 /g.
Claim 5
Dependent Claim
13 words
The method of claim 1 wherein said resulting solution is separated by filtration.
Claim 6
Dependent Claim
13 words
The method of claim 1 wherein said resulting solution is separated by decanting.
Claim 7
Independent Claim
84 words
The method of decreasing the uranium content of an aqueous HF solution containing a trace amount of uranium, said method comprising: mixing said solution with particulate calcium fluoride to provide a calcium fluoride-to-uranium weight ratio in the range of from about 8 to 75, said calcium fluoride having a nitrogen surface area in the range of from about 1 to 200 m 2 /g, to form uranium-bearing particulates, permitting said particulates to settle out of solution, and selectively recovering the resulting aqueous HF solution.
Claim 8
Independent Claim
84 words
The method of decreasing the uranium content of an aqueous HF solution containing a trace amount of uranium, said method comprising: mixing said solution with particulate calcium fluoride to provide a calcium fluoride-to-uranium weight ratio in the range of from about 8 to 75, said calcium fluoride having a nitrogen surface area in the range of from about 1 to 200 m 2 /g, to form uranium-bearing particulates, permitting said particulates to settle out of solution, and selectively recovering the resulting aqueous HF solution.
Claim 9
Dependent Claim
12 words
The method of claim 6 wherein said supernate is recovered by decanting.
Claim 10
Dependent Claim
12 words
The method of claim 6 wherein said supernate is recovered by filtration.
Claim 11
Dependent Claim
16 words
The method of claim 6 wherein the mixing and settling-out operations are conducted at room temperature.
Claim 12
Independent Claim
54 words
The method of decreasing the uranium content of an aqueous HF solution containing uranium without substantially altering the fluoride content thereof, said method comprising: mixing particulate calcium fluoride with said solution to form uranium-bearing particlates, permitting said particulates to sediment from said solution, and separating the resulting aqueous HF solution from the settled particulates.
Claim 13
Independent Claim
54 words
The method of decreasing the uranium content of an aqueous HF solution containing uranium without substantially altering the fluoride content thereof, said method comprising: mixing particulate calcium fluoride with said solution to form uranium-bearing particlates, permitting said particulates to sediment from said solution, and separating the resulting aqueous HF solution from the settled particulates.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1983-11-18 | 1984-05-19 | 1984-11-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1987-11-18 | 1988-05-19 | 1988-11-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1991-11-18 | 1992-05-19 | 1992-11-18 | $7700.00 | Window Closed / Lapsed |