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US3966872A Expired / Lapsed US ⏱️ 0.0 years remaining

Coupled cationic and anionic method of separating uranium

Assignee: Westinghouse Electric Corp
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Filing: 1973-11-01
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Granted: 1976-06-29
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Expires: 1993-11-01
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Abstract

Abstract Uranium is separated from contaminating metal ions in an aqueous feed liquor containing the uranyl ion. The liquor is extracted with a first, non-interfering, waterimmiscible, organic solvent containing a reagent which reacts with the uranyl ion to form a complex soluble in the organic solvent. The organic solvent is scrubbed with water if necessary, then stripped with a stripping liquor of an aqueous sulfuric acid liquor having a pH of about 0.5 to about 6 containing a reducing ion or an aqueous carbonate solution having a pH of about 8 to about 9. If the sulfuric acid liquor is used the stripped uranous ion is oxidized and the sulfuric acid liquor is diluted to prevent the precipitation of a uranium complex. The stripping liquor is extracted with an amine liquor comprising a second, noninterfering, water-immiscible, organic solvent and a tertiary or quaternary amine. The amine liquor is stripped with an ammonium carbonate solution to precipitate a uranium complex. The uranium complex is filtered off and may be calcined to produce U3O8 or UO2.

Inventors

  • 👤 Parameshwaran Sundar
  • 👤 Leonard Elikan
  • 👤 Ward L. Lyon

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-30 17:23
CPC Classifications
C; C22; C22B; C22B60/00; C22B60/02; C22B60/0204; C22B60/0217; C22B60/0252; C22B60/026; Y; Y02; Y02P; Y02P10/00; Y02P10/20

Claims Analysis

Total Claims: 39
Claim 1
Independent Claim 226 words
A method of separating uranium from contaminating ions in an aqueous feed liquor containing uranyl ion comprising: 1. extracting said feed liquor with a first, non-interfering, water-immiscible, organic solvent containing a reagent which reacts with said uranyl ion to form a complex soluble in said solvent; 2. either A. stripping said organic solvent with a stripping liquor of an aqueous carbonate solution having a pH of about 8 to about 9 and a molarity of about 0.25 to about 0.75 or B. (1) stripping said organic solvent with a stripping liquor of an aqueous sulfuric acid liquor having a pH of about 0.5 to about 5 containing a reducing ion, 2. oxidizing uranous ion in said sulfuric acid liquor to uranyl ion, and 3. adjusting the pH of said sulfuric acid liquor to about 0.9 to about 1.5; 3. extracting said stripping liquor with an amine liquor comprising a second, non-interfering, water-immiscible, organic solvent, about 0.1 to about 0.5 M of an amine having the formula N[R].sub.n where n is 3 to 4 and each R is independently selected from alkyl from C 7 to C 12 , and about 1 to about 10% by volume of a solubilizer; 4. stripping said amine with an ammonium carbonate solution containing sufficient ammonium and carbonate ions to precipitate a uranium complex; and 5. collecting said precipitated uranium complex.
Claim 2
Independent Claim 226 words
A method of separating uranium from contaminating ions in an aqueous feed liquor containing uranyl ion comprising: 1. extracting said feed liquor with a first, non-interfering, water-immiscible, organic solvent containing a reagent which reacts with said uranyl ion to form a complex soluble in said solvent; 2. either A. stripping said organic solvent with a stripping liquor of an aqueous carbonate solution having a pH of about 8 to about 9 and a molarity of about 0.25 to about 0.75 or B. (1) stripping said organic solvent with a stripping liquor of an aqueous sulfuric acid liquor having a pH of about 0.5 to about 5 containing a reducing ion, 2. oxidizing uranous ion in said sulfuric acid liquor to uranyl ion, and 3. adjusting the pH of said sulfuric acid liquor to about 0.9 to about 1.5; 3. extracting said stripping liquor with an amine liquor comprising a second, non-interfering, water-immiscible, organic solvent, about 0.1 to about 0.5 M of an amine having the formula N[R].sub.n where n is 3 to 4 and each R is independently selected from alkyl from C 7 to C 12 , and about 1 to about 10% by volume of a solubilizer; 4. stripping said amine with an ammonium carbonate solution containing sufficient ammonium and carbonate ions to precipitate a uranium complex; and 5. collecting said precipitated uranium complex.
Claim 3
Dependent Claim 49 words
A method according to claim 1 wherein said organic solvent is recycled to form a closed loop, said stripping liquor is recycled to form a closed loop, said amine liquor is recycled to form a closed loop, and said ammonium carbonate solution is recycled to form a closed loop.
Claim 4
Dependent Claim 52 words
A method according to claim 2 wherein when said stripping liquor is a sulfuric acid liquor at least about 17% by volume of said sulfuric acid liquor is not recycled after stripping and when said stripping liquor is a carbonate solution at least about 2% by volume is not recycled after stripping.
Claim 5
Dependent Claim 24 words
A method according to claim 1 wherein up to about 5% by volume of said ammonium carbonate solution is bled to said stripping liquor.
Claim 6
Dependent Claim 34 words
A method according to claim 1 wherein said aqueous feed liquor is a sulfuric acid, phosphoric acid, or sodium carbonate liquor and between steps (1) and (2) said organic solvent is scrubbed with water.
Claim 7
Dependent Claim 10 words
A method according to claim 1 wherein n is 3.
Claim 8
Dependent Claim 12 words
A method according to claim 1 wherein each R group is identical.
Claim 9
Dependent Claim 21 words
A method according to claim 7 wherein said amine is selected from the group consisting of tri-iso-octylamine, tri-n-octylamine, and mixtures thereof.
Claim 10
Dependent Claim 18 words
A method according to claim 1 wherein the concentration of said solubilizer is about 2 to about 5%.
Claim 11
Dependent Claim 20 words
A method according to claim 1 wherein said solubilizer is a monohydric alcohol from C 6 to C 12 .
Claim 12
Dependent Claim 23 words
A method according to claim 1 wherein the concentration of said ammonium and said carbonate ions is about 0.75 to about 3 M.
Claim 13
Dependent Claim 23 words
A method according to claim 11 wherein the concentration of said ammonium and said carbonate ions is about 2 to about 3 M.
Claim 14
Dependent Claim 29 words
A method according to claim 1 wherein said reagent has the general formula ##EQU1## where each R' is independently selected from alkyl from C 4 to C 10 .
Claim 15
Dependent Claim 13 words
A method according to claim 13 wherein said reagent is di-2-ethyl-hexyl phosphoric acid.
Claim 16
Dependent Claim 22 words
A method according to claim 14 wherein said solvent includes about 0.025 to about 0.25 moles per liter of a synergistic agent.
Claim 17
Dependent Claim 14 words
A method according to claim 15 wherein said synergistic agent is tri-octyl phosphine oxide.
Claim 18
Dependent Claim 21 words
A method according to claim 1 wherein said first and second solvents are linear hyrocarbons having 10 to 14 carbon atoms.
Claim 19
Dependent Claim 25 words
A method according to claim 1 wherein the concentration of said reagent is about 0.1 to about 1 mole per liter of said first solvent.
Claim 20
Dependent Claim 19 words
A method according to claim 1 wherein said collected uranium complex is calcined at about 350° to about 900°C.
Claim 21
Dependent Claim 25 words
A method according to claim 19 wherein said calcining is done in an oxidizing atmosphere to produce the mixed oxide U 3 O 8 .
Claim 22
Dependent Claim 20 words
A method according to claim 19 wherein said calcining is done in a reducing atmosphere to produce UO 2 .
Claim 23
Dependent Claim 79 words
A method according to claim 1 wherein the volume ratio of said feed liquor to said first organic solvent is about 0.1 to about 10, the volume ratio of said first organic solvent to said stripping liquor is about 0.1 to about 100, the volume ratio of said stripping liquor to said amine liquor is about 0.1 to about 1, and the volume ratio of said amine liquor to said ammonium carbonate solution is about 0.3 to about 1.
Claim 24
Dependent Claim 31 words
A method according to claim 1 wherein said stripping liquor is an aqueous carbonate solution, selected from the group consisting of solutions of ammonium carbonate, alkali metal carbonate, and mixtures thereof.
Claim 25
Dependent Claim 16 words
A method according to claim 23 wherein said aqueous carbonate solution is a sodium carbonate solution.
Claim 26
Dependent Claim 12 words
A method according to claim 1 wherein said uranium complex is ammonium-uranyl-tricarbonate.
Claim 27
Dependent Claim 31 words
A method according to claim 1 wherein said feed liquor is phosphoric acid containing about 0.1 to about 0.5 g/l of uranium and about 7 to about 15 g/l of iron.
Claim 28
Dependent Claim 25 words
A method according to claim 1 wherein the ratio by volume of said organic solvent to said stripping liquor is about 20 to about 35.
Claim 29
Dependent Claim 21 words
A method according to claim 1 wherein said aqueous sulfuric acid liquor has a pH of about 0.5 to about 1.5.
Claim 30
Dependent Claim 22 words
A method according to claim 1 wherein said reducing ion is ferrous ion in an amount of at least about 25 g/l.
Claim 31
Dependent Claim 32 words
A method according to claim 29 wherein said ferrous ion is obtained by the addition of elemental iron which is oxidized to the ferrous ion by reducing ferric ion to ferrous ion.
Claim 32
Dependent Claim 25 words
A method according to claim 30 wherein said sulfuric acid liquor is blanketed with a non-oxidizing gas to prevent the oxidation of said ferrous ion.
Claim 33
Dependent Claim 14 words
A method according to claim 1 wherein said uranous ion is oxidized with air.
Claim 34
Dependent Claim 23 words
A method according to claim 3 wherein additional sulfuric acid liquor is added to replace said sulfuric acid liquor which is not recycled.
Claim 35
Dependent Claim 38 words
A method according to claim 1 wherein the uranium concentration is lowered with water just prior to step (3) to about 50 to about 70% of the saturation concentration of the complex said uranium forms with said amine.
Claim 36
Dependent Claim 16 words
A method according to claim 1 wherein said amine concentration is about 0.1 to about 0.2M.
Claim 37
Dependent Claim 16 words
A method according to claim 10 wherein said solubilizer is n-octanol, n-decanol, or a mixture thereof.
Claim 38
Dependent Claim 18 words
A method according to claim 1 wherein the amount of said solubilizer is about 2 to about 5%.
Claim 39
Dependent Claim 19 words
A method according to claim 1 wherein said ammoniun carbonate solution contains about 1 to about 5% ammonium chloride.

References Cited (Backward Citations)

US2859094A Cited
US3083076A Cited
US3052513A Cited
US3835214A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1979-06-29 1979-12-29 1980-06-29 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1983-06-29 1983-12-29 1984-06-29 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1987-06-29 1987-12-29 1988-06-29 $7700.00 Window Closed / Lapsed

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