EP0100744B1 - Verfahren zur Extraktion von Uran aus Phosphorsäuren durch Alkylpyrophosphorsäuren - Google Patents

Verfahren zur Extraktion von Uran aus Phosphorsäuren durch Alkylpyrophosphorsäuren Download PDF

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Publication number
EP0100744B1
EP0100744B1 EP83420127A EP83420127A EP0100744B1 EP 0100744 B1 EP0100744 B1 EP 0100744B1 EP 83420127 A EP83420127 A EP 83420127A EP 83420127 A EP83420127 A EP 83420127A EP 0100744 B1 EP0100744 B1 EP 0100744B1
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EP
European Patent Office
Prior art keywords
uranium
process according
extraction
extraction process
acid
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired
Application number
EP83420127A
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English (en)
French (fr)
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EP0100744A1 (de
Inventor
Antoine Floreancig
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Uranium Pechiney
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Uranium Pechiney
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Publication of EP0100744A1 publication Critical patent/EP0100744A1/de
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Classifications

    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22B—PRODUCTION AND REFINING OF METALS; PRETREATMENT OF RAW MATERIALS
    • C22B60/00—Obtaining metals of atomic number 87 or higher, i.e. radioactive metals
    • C22B60/02—Obtaining thorium, uranium, or other actinides
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22B—PRODUCTION AND REFINING OF METALS; PRETREATMENT OF RAW MATERIALS
    • C22B60/00—Obtaining metals of atomic number 87 or higher, i.e. radioactive metals
    • C22B60/02—Obtaining thorium, uranium, or other actinides
    • C22B60/0204—Obtaining thorium, uranium, or other actinides obtaining uranium
    • C22B60/0217—Obtaining thorium, uranium, or other actinides obtaining uranium by wet processes
    • C22B60/0252—Obtaining thorium, uranium, or other actinides obtaining uranium by wet processes treatment or purification of solutions or of liquors or of slurries
    • C22B60/026—Obtaining thorium, uranium, or other actinides obtaining uranium by wet processes treatment or purification of solutions or of liquors or of slurries liquid-liquid extraction with or without dissolution in organic solvents

Definitions

  • the invention relates to an improved process for extracting by means of an agent, consisting of alkylpyrophosphoric acids, uranium present in phosphoric acid solutions, process which makes it possible to conserve over time the extraction power of said agent in limiting its degradation.
  • alkylpyrophosphoric acids as uranium extraction agent, used in a form dissolved in an organic diluent, such as that petroleum cut, kerosene, etc., the most commonly used extraction agent being alkylpyrophosphoric acid obtained by reaction of P 2 0 5 with octanol 2.
  • recovering the uranium contained in phosphoric acid at a rate of 90 to 200 milligrams of uranium oxide U 3 0 8 per liter consists first of all in contacting the solution of phosphoric acid with the extraction agent most commonly constituted by octylpyrophosphoric acid in solution in kerosene, the extraction of uranium being carried out against the current in a group of mixing and sedimentation tanks cascade.
  • the organic phase containing in solution the octylpyrophosphoric acid loaded with uranium, separated from the phosphoric acid solution, is treated by contact using hydrofluoric acid, giving fluoride d uranium (UF 4 ) and desuranic octylpyrophosphoric acid.
  • alkylpyrophosphoric acids as uranium extraction agent, and in particular octylpyrophosphoric acid, lies in the fact of their strong extracting power, even when they are used in organic solution very diluted, allowing them to extract, with a very good yield, the uranium present, even in very small quantity, in solutions of phosphoric acids.
  • 2423545 describes a process for extracting uranium from phosphoric acid solutions, the extracting agent of which is a pyrophosphoric acid diester such as dicaproyl pyrophosphate or dioctyl pyrophosphate, a process according to which the hydrolysis of said extracting agent would be greatly reduced, while the re-extraction of the uranium present in the organic phase is carried out by means of an alkaline solution and no longer by l hydrofluoric acid.
  • the extracting agent of which is a pyrophosphoric acid diester such as dicaproyl pyrophosphate or dioctyl pyrophosphate
  • the licensee thanks to her research, found and developed an improved process for extracting uranium contained in solutions of phosphoric acids, means of an extraction agent chosen from the group of alkylpyrophosphoric acids which makes it possible to avoid their degradation by acid hydrolysis, while retaining their extracting power.
  • the process according to the invention for the extraction of uranium contained in phosphoric acid solutions by means of an extraction agent consisting of an alkylpyrophosphoric acid, which consists in bringing the mineral phase of phosphoric acid and an organic phase containing the extraction agent by creating an emulsion is characterized in that, in an extraction unit comprising n stages in cascade with n> 1, for each extraction stage, the emulsion is produced during a first step by simultaneously subjecting the two phases for a time T, to an intense mechanical shearing action corresponding to a shear coefficient of at least 5000 s -1 in order to increase the contact surfaces between these two phases, then said emulsion during a second step is suddenly broken in a time T z , the total time required for the completion of the two steps being at most 20 minutes.
  • the extraction unit has a number of stages n of between 2 and 20.
  • this shear coefficient is chosen in the interval 5000 s -1 to 50,000 s -1 , but preferably in the interval 10,000 s -1 to 25,000 s -1 .
  • the total time required to carry out the two stages according to the invention is preferably at most equal to 10 minutes for an extraction stage.
  • the times T, and T of execution of the two stages can vary within wide limits, their ratio T, / T 2 being able to be chosen within the limits 1/100 to 5/1 and preferably within limits 1 / 25 to 2/1.
  • the emulsion between the two organic and mineral phases is produced by any means known to those skilled in the art, making it possible to quickly and vigorously obtain the finest emulsion possible, in order to multiply the surfaces of contact and obtain a very high extraction yield.
  • the rapid separation of the organic and mineral phases can be obtained by physical means using any known means allowing rapid rupture of said emulsion.
  • the extracting agent, entrained by the desuranic phosphoric acid can be recovered by a physical separation of centrifugation for example and joined to the recycled extraction agent after re-extraction of the uranium .
  • the uranium extracting agent is chosen from the well-known group of alkylpyrophosphoric acids, the alkyl radical of which is a carbon chain corresponding to the C 7 to C 13 alcohols obtained by oxo synthesis , such as for example octanol 2, ethylhexanol, cancanol.
  • the preparation of alkylpyrophosphoric acid can be carried out in a known manner by adding P 2 O 5 to the abovementioned alcohol, used alone or as a mixture with a hydrocarbon.
  • the temperature for preparing alkylpyrophosphoric acid is generally between 30 ° C and 80 ° C, but preferably between 30 ° C and 40 ° C.
  • the uranium extracting agent is generally dissolved in an aliphatic and / or aromatic hydrocarbon, such as kerosene for example.
  • the mixture thus formed constitutes the organic phase of extraction of the uranium, which contains from 5 to 100 g / l but preferably from 20 to 50 g / l of alkylpyrophosphoric acid.
  • the phosphoric acid solutions resulting from the attack on phosphate ores generally contain from 30 to 200 milligrams of uranium per liter, this uranium being partly in the form U IV and for the other in the form U VI.
  • the uranium VI is then reduced to uranium IV by the treatment of phosphoric acid solutions with iron, in the form of powder when the reduction treatment is carried out in a reactor or also in the form of scrap metal when the reduction treatment takes place in a column.
  • the phosphoric acid solutions containing suspended solids are subjected to a separation operation, before being brought into contact with the extractant in solution in an aliphatic hydrocarbon. and / or aromatic.
  • the two mineral and organic phases to be extracted and extracting are then brought into intimate contact in the form of a fine emulsion which is quickly broken in order to separate the organic phase loaded with uranium from the mineral phase with deuranied acid.
  • the organic phase loaded with uranium is then treated with an aqueous hydrofluoric acid solution, this solution containing 10 to 20%, but preferably 14 to 18% by weight of free HF.
  • the temperature at which the uranium is re-extracted by hydrofluoric acid is between 0 ° C and 60 ° C but preferably between 10 ° C and 30 ° C, temperature at which the degradation of the alkylpyrophosphoric acid remains low (less than 2%).
  • the uranium then precipitates in the form of UF 4 , which is separated from the liquid medium by any means chosen from those known to those skilled in the art.
  • the desuranized alkylpyrophosphoric acid is then recycled directly to the extraction of the uranium contained in the solutions of phosphoric acids after possible recharging with new alkylpyrophosphoric acid, while the solutions of desuranic phosphoric acids are themselves subjected to centrifugation to recover the mechanically driven extractant.
  • This example illustrates the method of extracting uranium according to the invention, using alkylpyrophosphoric acids compared to the extraction method most commonly used in the processes belonging to the prior art.
  • This acid is reduced either by powdered iron in a stirred tank for tests 1 to 4, or in a column by plate iron for tests 5 and 6.
  • the reduced phosphoric acid contains Fe II and Fe III in an Fe II / Fe III ratio between 5 and 5.3.
  • the phosphoric acid is treated with the extracting agent in solution in kerosene at a rate of 30 g / l.
  • the reduced phosphoric acid flow rate was 200 l / h while that of the extractant solution was 20 l / h.
  • the desuranized solvent was recycled to extraction after adding a fraction of an hour of the extractant.
  • Test No. 1 which illustrates the prior art, was carried out in an industrial installation whose extraction unit consisted of a battery of 4 mixer-settlers - extraction unit in which the cumulative times T 1 and T 2 for 4 stages as defined in the method according to the invention, is equal to 14 hours.
  • Test No. 2 illustrating the invention was carried out in an industrial installation, the extraction unit of which consisted of a 4-stage multi-stage centrifugal extractor, rotating at the speed of 2800 rpm, a unit in which the accumulation residence times T, and T z for 4 stages was less than two minutes.
  • Test No. 3 illustrating the prior art, differs from test No. 1 in the nature of the extractant which in this case was a solution of ethylhexylpyrophosphoric acid.
  • Test No. 4 illustrating the invention, differs from test No. 2 in the nature of the extractant which was ethylhexylpyrophosphoric acid.
  • Test No. 5 illustrating the prior art, differs from test No. 1 only in the mode of reduction of phosphoric acid (on platelets in column).
  • Test N ° 6 illustrating the invention, differs from test N ° 2 by the mode of reduction of phosphoric acid and by the constitution of the extraction unit which included four single stage centrifugal extractors in battery - unit in which the cumulative residence times T, and T 2 was less than two minutes.
  • This example illustrates the method of extracting uranium according to the invention, using alkylpyrophosphoric acids, compared to the extraction method most commonly used in methods belonging to the prior art.
  • the phosphoric acid treated had the following composition:
  • Test No. 7 which illustrates the prior art, was carried out like test 1, in a battery of 4 mixer-settlers.
  • Test No. 8 which illustrates the invention, was carried out like test 2, but using a battery comprising 3 single-stage centrifugal extractors.

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  • Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • General Life Sciences & Earth Sciences (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Geology (AREA)
  • Manufacturing & Machinery (AREA)
  • Environmental & Geological Engineering (AREA)
  • Materials Engineering (AREA)
  • Mechanical Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Extraction Or Liquid Replacement (AREA)
  • Manufacture And Refinement Of Metals (AREA)

Claims (17)

1.Verfahren zur Extraktion des in phosphorsauren Lösungen enthaltenen Urans mit Hilfe eines aus einer Alkylpyrophosphorsäure bestehenden Extraktionsmittels, das darin besteht, die mineralische Phosphorsäurephase unter Rühren in Kontakt mit einer das Extraktionsmittel enthaltenden organischen Phase unter Schaffung einer Emulsion zu bringen, dadurch gekennzeichnet, dass in einer eine oder mehrerer Stufen in Kaskade aufweisenen Extraktionseinheit die Emulsion für jede Extraktionsstufe in einem ersten Schritt erzeugt wird, in dem man gleichzeitig die beiden, die Phosphorsäure und das Extraktionsmittel enthaltenden Phasen während einer Zeit T1 einer starken, einem Scherkoeffizient von wenigstens 5000 s-1 entsprechenden mechanischen Scherwirkung mit dem Ziel einer Vervielfachung der Kontaktoberflächen zwischen diesen beiden Phasen unterwirft und dann die Emulsion in einem zweiten Schritt in einer Zeit Tz heftig gebrochen wird, wobei die Summe T1+T2 der zur Durchführung der zwei Schritte erforderlichen Zeiten höchstens 20 Minuten ist.
2. Verfahren zur Extraktion des Urans nach Anspruch 1, dadurch gekennzeichnet, dass die Extraktionseinheit eine Stufenzahl im Bereich von 2 bis 20 aufweist.
3. Verfahren zur Extraktion des Urans nach Anspruch 1, dadurch gekennzeichnet, dass die Extraktionseinheit eine einzige Stufe aufweist.
4. Verfahren zur Extraktion des Urans nach irgendeinem der Ansprüche 1 bis 3, dadurch gekennzeichnet, dass der Scherkoeffizient im Bereich von 5000 s-1 bis 50000 s-1 gewählt wird.
5. Verfahren zur Extraktion des Urans nach Anspruch 4, dadurch gekennzeichnet, dass der Scherkoeffizient im Bereich von 10000 s-1 bis 25000 s-1 gewählt wird.
6. Verfahren zur Extraktion des Urans nach irgendeinem der Ansprüche 1 bis 4, dadurch gekennzeichnet, dass die Summe T1 +T2 der zur Durchführung der beiden Schritte erforderlichen Zeiten höchstens gleich 10 Minuten für eine Extraktionsstufe ist.
7. Verfahren zur Extraktion des Urans nach irgendeinem der Ansprüche 1 bis 6, dadurch gekennzeichnet, dass das Verhältnis T1/T2 der Durchführungszeiten der beiden Schritte für eine Extraktionsstufe in den Grenzen von 1 /100 bis 5/1 gewählt wird.
8. Verfahren zur Extraktion des Urans nach Anspruch 7, dadurch gekennzeichnet, dass das Verhältnis T1/T2 in den Grenzen von 1/25 bis 2/1 gewählt wird.
9. Verfahren zur Extraktion des Urans nach irgendeinem der Ansprüche 1 bis 7, dadurch gekennzeichnet, dass das Extraktionsmittel, das eine Alkylpyrophosphorsäure ist, durch Zusatz von P205 zu einem Alkohol mit einer Kohlenstoffkette von C7 bis C13 erhalten wird.
10. Verfahren zur Extraktion des Urans nach Anspruch 9, dadurch gekennzeichnet, dass die Temperatur zum Erhalten der Alkylpyrophosphorsäure im Bereich von 30° C bis 80° C liegt.
11. Verfahren zur Extraktion des Urans nach Anspruch 10, dadurch gekennzeichnet, dass die Temperatur im Bereich von 30° C bis 40° C liegt.
12. Verfahren zur Extraktion des Urans nach irgendeinem der Ansprüche 1 bis 10, dadurch gekennzeichnet, dass die mit Uran beladene, vom zweiten Schritt stammende organische Phase mit einer Flusssäurelösung zur Reextraktion des Urans behandelt wird.
13. Verfahren zur Extraktion des Urans nach Anspruch 12, dadurch gekennzeichnet, dass die Flusssäurelösung gewichtsmässig 10 bis 20% HF enthält.
14. Verfahren zur Extraktion des Urans nach Anspruch 13, dadurch gekennzeichnet, dass die Lösung gewichtsmässig 14 bis 18% H enthält.
15. Verfahren zur Extraktion des Urans nach Anspruch 12, dadurch gekennzeichnet, dass die Temperatur, bei der die Reextraktion des Urans durch die Flusssäure erfolgt, im Bereich von 0° C bis 60° C liegt.
16. Verfahren zur Extraktion des Urans nach Anspruch 15, dadurch gekennzeichnet, dass die Temperatur im Bereich von 10° C bis 30° C liegt.
17. Verfahren zur Extraktion des Urans nach irgendeinem der Ansprüche 1 bis 15, dadurch gekennzeichnet, dass man durch Zentrifugieren das durch die Phsophorsäure mitgerissene Extraktionsmittel wiedergewinnt.
EP83420127A 1982-07-30 1983-07-20 Verfahren zur Extraktion von Uran aus Phosphorsäuren durch Alkylpyrophosphorsäuren Expired EP0100744B1 (de)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
FR8213820 1982-07-30
FR8213820A FR2531102B1 (fr) 1982-07-30 1982-07-30 Procede d'extraction de l'uranium des acides phosphoriques par les acides alkylpyrophosphoriques

Publications (2)

Publication Number Publication Date
EP0100744A1 EP0100744A1 (de) 1984-02-15
EP0100744B1 true EP0100744B1 (de) 1985-12-18

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ID=9276723

Family Applications (1)

Application Number Title Priority Date Filing Date
EP83420127A Expired EP0100744B1 (de) 1982-07-30 1983-07-20 Verfahren zur Extraktion von Uran aus Phosphorsäuren durch Alkylpyrophosphorsäuren

Country Status (16)

Country Link
US (1) US4510122A (de)
EP (1) EP0100744B1 (de)
KR (1) KR870002187B1 (de)
BR (1) BR8304067A (de)
CA (1) CA1209808A (de)
ES (1) ES8404419A1 (de)
FI (1) FI832749A (de)
FR (1) FR2531102B1 (de)
GR (1) GR78860B (de)
IL (1) IL69342A (de)
JO (1) JO1260B1 (de)
MA (1) MA19852A1 (de)
OA (1) OA07505A (de)
PH (1) PH19136A (de)
PT (1) PT77136B (de)
YU (1) YU157783A (de)

Families Citing this family (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2573415B1 (fr) * 1984-11-16 1986-12-12 Pechiney Uranium Procede de recuperation sous forme de fluorure tetravalent de l'uranium extrait de solutions phosphatees
US5463177A (en) * 1994-08-23 1995-10-31 General Electric Company Solvent extraction process
KR100675919B1 (ko) * 2005-11-08 2007-06-04 정영기 원심분리기를 이용한 우라늄 동위원소 분리방법
US8883096B2 (en) 2008-07-31 2014-11-11 Urtek, Llc Extraction of uranium from wet-process phosphoric acid
US8226910B2 (en) * 2008-07-31 2012-07-24 Urtek, Llc Extraction of uranium from wet-process phosphoric acid

Family Cites Families (13)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2847275A (en) * 1955-01-04 1958-08-12 James H Yeager Uranium recovery process
GB860428A (en) * 1958-01-29 1961-02-08 Ca Atomic Energy Ltd Liquid-liquid contact extractor
US3416320A (en) * 1967-07-14 1968-12-17 Exxon Research Engineering Co Turbo-jet propulsion method using emulsified fuels and demulsification
GB1596410A (en) * 1976-12-27 1981-08-26 Exxon Research Engineering Co Liquid membranes and process for uranium recovery therewith
FR2376688A1 (fr) * 1977-01-10 1978-08-04 Anglian Water Authority Procede et appareil pour former une dispersion aqueuse stable de produits a base de silicate
US4180545A (en) * 1977-03-25 1979-12-25 Tennessee Valley Authority Uranium recovery from wet-process phosphoric acid
US4154698A (en) * 1977-06-08 1979-05-15 Nalco Chemical Company Resolution of oil-in-water emulsions containing uranium
FR2423545A1 (fr) * 1977-08-25 1979-11-16 Minemet Rech Sa Procede pour la recuperation de l'uranium contenu dans des solutions phosphatees
US4243637A (en) * 1977-10-11 1981-01-06 Occidental Petroleum Company Uranium recovery from pre-treated phosphoric acid
US4311676A (en) * 1978-09-08 1982-01-19 Minemet Recherche Process for the recovery of uranium contained in phosphated compounds
US4293529A (en) * 1978-10-27 1981-10-06 Uranium Recovery Corporation Process for recovering uranium from wet-process phosphoric acid using alkyl pyrophosphoric acid extractants
US4292278A (en) * 1979-02-21 1981-09-29 Wyoming Mineral Corp. Purification of wet process phosphoric acid as a pretreatment step in the recovery of uranium
US4287071A (en) * 1979-10-10 1981-09-01 Occidental Research Corporation Simultaneous extraction of more than one ion by liquid membrane process

Also Published As

Publication number Publication date
ES524587A0 (es) 1984-05-01
KR840005414A (ko) 1984-11-12
BR8304067A (pt) 1984-03-07
PT77136A (fr) 1983-08-01
PH19136A (en) 1986-01-10
FR2531102A1 (fr) 1984-02-03
FR2531102B1 (fr) 1986-08-14
EP0100744A1 (de) 1984-02-15
FI832749A0 (fi) 1983-07-29
IL69342A (en) 1986-07-31
US4510122A (en) 1985-04-09
JO1260B1 (en) 1985-04-20
GR78860B (de) 1984-10-02
PT77136B (fr) 1986-01-24
YU157783A (en) 1986-04-30
ES8404419A1 (es) 1984-05-01
KR870002187B1 (ko) 1987-12-28
FI832749A (fi) 1984-01-31
MA19852A1 (fr) 1984-04-01
OA07505A (fr) 1985-03-31
CA1209808A (fr) 1986-08-19

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