OA16901A - Extraction of uranium from wet-process phosphoric acid. - Google Patents

Abstract

In a preferred embodiment, a process for extracting uranium from wet-process phosphoric acid (WPA), comprises separating uranium from WPA to produce a loaded uranium solution stream and a uranium depleted WPA stream. The loaded uranium solution stream is then contacted by with an ion exchange resin. Uranium species bound to the ion exchange resin are eluted by contacting the resin with a solution comprising anions to produce a loaded uranium eluant stream. The loaded uranium eluant stream is treated to provide a uranium containing product.

Description

This daims the benefit of U.S. Provlsîonal Application No. 61/553,742 filed on October 31, 2011 and titled Uranium Extraction Processes and is a continuation-in-part of U.S Application No. 13/931,112 filed on July 23, 2012 and titled Extraction of Uranium from Wet-Process Phosphoric Acid and U.S Application No. 13/555,606 filed on July 23, 2012 and titled Extraction of Uranium from Wet-Process Phosphoric Add, which both claim the benefit of U.S Application No. 12/510,294 (now U.S. Pat. No. 8,226,910) filed on July 28, 2009 and titied Extraction of Uranium from Wet-Process Phosphoric Add, which daims the benefit of U.S. Provlsional Application No. 61/161,133 filed March 18, 2009 and U.S. Provisional Application No. 61/085,177 filed July 31, 2008. Each of these référencés Is incorporated herein by référencé In Its entirety.

FIELD OF THE INVENTION

The invention relates to the field of extracting uranium from wet-process phosphoric add.

BACKGROUND

Phosphoric add (H₃PO₄) for use in fertiiizer production is typically produced by a wet-process during which naturally occurring phosphate rock Is reacted with sulphuric acid to provide so called wet-process phosphoric add (WPA). Depending on the source of the phosphate rock, it may contain valuable metals such as uranium, vanadium and yttrium, which are dissolved by the sulphuric add and form lmpurity constitueras of the WPA.

In the United States, plants hâve been In operation since the early 1950's to recover vaiuable amounts of uranium from WPA. However, with fluctuations in the spot price of uranium It is Important that It can be extracted from the WPA In a cost-effective manner. To date, many of the plants that hâve operated uranium extraction processes hâve utilized solvent extraction process to extract the uranium from the WPA. Another process that has received greater attention in recent times 1s an ion exchange process whereby WPA containing uranium is ioaded onto an Ion exchange resin. The WPA Is flushed from the resin, leaving the uranium bound to the resin. The uranium is then eiuted from the resin. United States patent No. 4,599,221 (Ketzinel et al.) disdoses such a process for extracting uranium from WPA using an Ion exchange process.

Unfortunately, the known uranium extraction processes are not ail that simple to carry out. Part of the problem is that the WPA Is a crude material containing a range of organic and Inorganic contaminants or species that can Interfère with the extraction process and hâve a profound effect on the commercial viability of the process.

The applicant has previously discovered that certain process efficiencies are achieved by lowering the iron concentration of the WPA, reducing the valency of any remalning ferrie iron in the WPA to ferrous Iron, and then extracting uranium compounds from the WPA. These details are disclosed In U.S. Pat. No. 8,226,910, which Is Incorporated by reference In Its entirety.

There remains a need for other Improved processes for extracting uranium from WPA that overcome one or more of the problème associated with others* processes and/or that are more efficient.

SUMMARY

In a first aspect, the Invention provides a process for extracting uranium from wet-process phosphoric acid (WPA), the process comprising: (a) separating uranium from WPA to produce a loaded uranium solution stream and a uranium depleted WPA stream; (b) contacting the loaded uranium solution stream with an Ion exchange resin; (c) eluting uranium species bound to the Ion exchange resin by contacting the resin with a solution comprising anions to produce a loaded uranium eluant stream; and (d) treating the loaded uranium eluant stream to provide a uranium containing product.

In some embodiments, the anions used to elute the uranium species In step (c) are selected from the group consisting of chloride anions, sulphate anions, nitrate anions, and combination thereof.

In some embodiments of the first aspect of the Invention, step (a) Is preceded by a valency réduction step comprising reducing the valency of ferrie Ions In the WPA. The valency réduction step may be carried out by chemical réduction, such as by the addition of metallic Iron, ferrophosphorus alloy or ferro-silicon alloy; or by electrochemical réduction (ER).

In some embodiments of the first aspect of the invention, step (a) and/or the valency réduction step (if used) may be preceded by an iron removal step. The Iron removal step comprises lowering the concentration of Iron In the WPA by decreasing the amount of dissolved Iron species In the WPA relative to the amount of uranium species In the WPA to produce a lowered Iron content WPA having uranium species thereln. The concentration of Iron In the WPA may be lowered by precipltating at least some of the Iron présent in the WPA as Iron ammonium phosphate.

In a second aspect, the Invention provides a process for extracting uranium from wet-process phosphoric acid (WPA), the process comprising: (a) contacting uranium laden WPA with a first ion exchange resin to form uranium depleted WPA; (b) separating the uranium depleted WPA from the first ion exchange resin; (c) oxidizing uranium species on the first ion exchange resin by contacting the first ion exchange resin with an oxidant; (d) contacting the first ion exchange resin with ammonia to remove impurities from the resin, the impurities being vanadium ions, organic species, or a combination thereof; (e) separating the impurities from the first ion exchange resin; (f) removing the oxidized uranium species from the first ion exchange resin by contacting the resin with ammonium carbonate to form a uranium enriched ammonium carbonate stream; (g) contacting the uranium enriched ammonium carbonate stream with a second ion exchange resin to form uranium depleted ammonium carbonate; (h) separating the uranium depleted ammonium carbonate from the second ion exchange resin; and (i) eluting uranium species from the second ion exchange resin toform a uranyl solution.

In some embodiments, the oxidant is selected from the group consisting of: air, oxygen, hydrogen peroxide, WPA, and combinations thereof.

ln some embodiments, the elution in step (i) Is carried out using a solution comprising anions selected from the group consisting of chloride anions, nitrate anions, sulphate anions, and combinations thereof.

ln some embodiments of the second aspect of the invention, step (a) may be preceded by a valency réduction step comprising reducing the vaiency of ferrie ions ln the WPA. The valency réduction step may be carried out by chemical réduction, such as by the addition of metallic Iron, ferro-phosphorus alloy or ferro-silicon alloy; or by eiectrochemical réduction (ER).

ln some embodiments of the second aspect of the Invention, step (a) and/or the valency réduction step (if used) may be preceded by an Iran removal step. The iron removal step comprises lowering the concentration of iron in the WPA by decreaslng the amount of dissolved iron species in the WPA relative to the amount of uranium species in the WPA to produce a lowered iron content WPA having uranium species therein. The concentration of Iran ln the WPA may be lowered by preclpitating at least some of the iron présent ln the WPA as iron ammonium phosphate.

in a third aspect, the Invention provides a process for extracting uranium from wet-process phosphoric add (WPA), the process comprising: (a) contacting uranium laden WPA with an oxidant to form an oxidized WPA stream; (b) contacting the oxidized WPA stream with an organic solvent; (c) separating a uranium enriched organic solvent stream from an aqueous WPA stream; (d) contacting the uranium enriched organic solvent stream with an ammonium carbonate stream to form a uranium enriched ammonium carbonate stream; (e) contacting the uranium enriched ammonium carbonate stream with an ion exchange resin; (f) separating a uranium depieted ammonium carbonate stream from the Ion exchange resin; (g) contacting the ion exchange resin with a solution comprising chloride ions; and (h)separating a uranyl solution from the ion exchange resin.

In some embodiments, the organic solvent used in step (b) comprises a di(25 ethylhexyl)phosphoric acid and trioctylphosphlne oxide (i.e. a DEHPA TOPO system).

In some embodiments of the third aspect of the invention, the valency réduction step is preceded by an Iron removal step. The iron removal step comprises lowering the concentration of iron In the WPA by decreasing the amount of dissolved Iron species In the WPA relative to the amount of uranium species in the WPA to produce a lowered Iron content WPA having 10 uranium species therein. The concentration of Iron In the WPA may be lowered by precipitating at least some of the iron présent in the WPA as Iron ammonium phosphate.

In some embodiments of any of the first, second, or third aspects of the invention, the uranyl solution may be further treated to provide a uranium containing product. The further treatment may comprise a précipitation step.

BRIEF DESCRIPTION OF DRAWINGS

For a further understanding of the Invention, reference is made to the following detailed description, taken In connection with the accompanying drawings illustrating various embodiments of the présent Invention, in which:

FIG. 1 Illustrâtes a general flow chart for a process according to a first exemplary embodiment of the Invention;

FIG. 2 illustrâtes a general flow chart for a process according to a second exemplary embodiment of the invention;

FIG. 3 illustrâtes a general flow chart for a process according to a third exemplary embodiment 25 of the Invention;

FIG. 4 illustrâtes a general flow chart for a process according to a fourth exemplary embodiment of the Invention;

FIG. 5 illustrâtes a general flow chart for a process according to a flfth exemplary embodiment of the invention; and

FIG. 6 illustrâtes a general flow chart for a process according to a sixth exemplary embodiment of the invention.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

The Invention will now be described with référencé to the accompanying drawings in which preferred embodiments of the invention are shown. The invention may, however, be embodied in many different forms and should not be construed as limited soiely to the embodiments described herein.

FIG. 11s a flow ch art of a first exemplary embodiment of the Invention, which is a process 10 for extracting uranium from wet-process phosphoric acid (WPA) 12. The process 10 comprises a first séparation step 14 in which uranium Is separated from the WPA in a first ion exchange (IX) or solvent extraction (SX) step. The first séparation step 14 provides a loaded uranium solution stream 16 and a uranium depleted WPA stream 18. The loaded uranium solution stream 16 is then contacted with an anion exchange resin In a secondary Ion exchange step 20. During the ion exchange step 20 uranium species are bound to the anion exchange resin. The bound uranium species are then eluted from the anion exchange resin by contactîng the resin with a solution comprising chloride Ions 22 to produce a loaded uranium eluant stream 24. Other anlons that couid be used to elute the bound uranium species from the anion exchange resin include nitrate and sulphate. In some embodiments, the secondary Ion exchange step 20 may be carried out using a cation exchange resin or a cheiating resin. The loaded uranium eluant stream 24 Is then treated in a further treatment step 26 to provide a uranium containing product

28.

The wet-process phosphoric acid (WPA) 12 may be any WPA feed. WPA is typically produced by reacting phosphate rock with sulphuric acid Prior to It being fed Into the process of the présent invention, the WPA may be treated In one or more pre-treatment steps. For example, the WPA feed 12, at a concentration of approximately 30% WPA may contain a significant amount of suspended solids, mostly sodium fluorosilicates and gypsum, which may cause Issues for later stages of the process. In these cases, the WPA may be clarified. The clarification step may comprise filtering the WPA to remove insoluble matter. Specifically, the clarification step may use an existîng clarifier In a WPA plant and additional clarifiera, compiementing the pre-exlsting clarifiera, are used to reduce the total suspended solids (TSS) and decrease process fluctuations due to upstream changes. In these embodiments, WPA can, for Instance, be clarified in conventional clarifiera. The clarifiera are dosed with flocculant to encourage précipitation of suspended solids. Underflow from the clarifier may be transferred back to the clarifier with the overflow being transferred to the next stage of the process.

Preferably, the WPA 12 Is an aqueous solution comprising from about 20% by weight to about 40% by weight WPA. In some embodiments, the WPA 12 is an aqueous solution comprising about 30% by weight WPA.

The first séparation step 14 may be an ion exchange (IX) step or a solvent exchange (SX) step.

In some embodiments, the first séparation step 14 is an Ion exchange step. WPA feed 12 (which may or may not be a lowered iron content WPA or a valency reduced WPA as described in more détail below) Is transferred to one or more ion exchange (IX) columns containing a chelating ion exchange resin. Typically, each train of IX columns will nominally hâve one iead column, one catch (or taii) column and one column In elution/idle mode at any one time. The uranium depleted WPA stream 18 is retumed to WPA holding tanks to be used for fertilizer production, etc.

Once one of the IX columns In the train Is loaded it is taken offline and eluted. The elution procedure comprises elutlng the IX column with eight Bed Volumes (BV) of ammonium carbonate solution. Uranium forms a stable, soluble uranyl bicarbonate complex in the ammonium carbonate solution, whereas Impurities such as Iron wili form Insoluble compounds. Precipitated Iran can be removed from the eluate using filters prior to entering secondary IX where further réjection of Impurities takes place. The loaded uranium solution stream 16 containing uranyl carbonate from the first séparation step 14 is then passed to the secondary anion exchange step 20, to extract the uranium onto the resin, and to recycle the ammonium carbonate. If necessary, a nominal 10% bleed may be removed to control impurity build up In the eluant and may be replaced with fresh ammonium carbonate solution. The uranium bound to the IX column In the secondary anion exchange step 20 is then eluted using a solution containing chloride Ions 22 to produce a uranium containing product 28. Other anlons that can be used for this step Include sulphate and nitrate.

In some other embodiments, the first séparation step 14 Is a solvent extraction step. WPA feed 12 (which may or may not be a lowered iron content WPA or a valency reduce WPA as described In more detail below) may be transferred to an oxidation stage in which the WPA Is oxidized with an air/oxygen mixture and/or with a chemical oxidant, such as hydrogen peroxide or a WPA stream. The oxidized WPA is then transferred to a solvent extrader. The solvent extraction step 14 uses any organic solvent that has a high affinity for uranium. Examples of solvents of this type include a DEHPA TOPO (di-2-ethylhexyl phosphoric acid and trioctylphosphlne oxide) system. In some embodiments, the solvent extraction step 14 Is a multi-extraction DEHPA TOPO (di-2-ethylhexyl phosphoric acid and trioctylphosphine oxide) system, nominally with a concentration of 0.5M DEHPA and 0.125M TOPO in a kerosene based organic diluent, operated at around 40Ό. Further details of the DEHPA TOPO can be found In Hurst et al., Ind. Eng. Chem. Process Des. Develop., 1972,11, 122-128, the details of which are Incorporated herein by reference. The uranium depleted WPA stream 18 Is retumed to WPA holding tanks to be used for fertiîizer production, etc.

In some embodiments, the prégnant organic phase is stripped with ammonium carbonate to provided loaded uranium solution stream 16.

The process described in relation to FIG. 1 may be varied to add additional steps as required. For example, different sources of phosphate rock hâve different compositions. As a resuit, feed streams of WPA from different sources of phosphate rock wiil typically hâve different impurities, any of which' may interfère with the uranium extraction process. Consequently, further steps may be incorporated into the process of the présent invention to improve the efficiency of the uranium extraction. Some further embodiments of the process of the présent Invention incorporating the further steps will now be described.

FIG. 2 is a flow chart describing a second exemplary embodiment of the invention which Is a process 40 for extracting uranium from wet-process phosphoric acid (WPA) 12. The process 40 comprises contacting uranium laden WPA 12 with a first ion exchange resin In a first ion exchange step 42. The first ion exchange resin is a chelating resin. A uranium depleted WPA stream 44 is separated from the first ion exchange resin and the resîn Is then contacted with an oxldant 52 in an oxidation step 54 under conditions to oxidize substantially ail of the uranium species on the resin. The first ion exchange resin is then contacted with a stream comprising ammonia 46 in a stripping step 48 under conditions to remove at least some of any bound vanadium ions and/or organic species from the resin. A vanadium and/or organic species enriched stream 50 Is then separated from the first ion exchange resin. The first ion exchange resin is subsequently contacted with an ammonium carbonate stream 56 In an elution step 58 under conditions to remove the oxidized uranium species from the resin and provide a uranium enriched ammonium carbonate stream 60. The uranium enriched ammonium carbonate stream 60 is then contacted with an anion exchange resin in a second Ion exchange step 62 and a uranium depleted ammonium carbonate stream 64 Is separated from the second ion exchange resin. The uranium species are then eluted from the second Ion exchange resin in an elution step 66 to provide a uranyl solution 68. The elution step 66 may be carried out using a solution comprising suitable anions, such as chloride, nitrate or sulphate.

FIG. 3 Is a flow chart describing a third exemplary embodiment of the invention which is a process 40 for extracting uranium from wet-process phosphoric acid (WPA) 12. Process steps 42, 48, 54, 58, 62 and 64 In this embodiment are the same as those described in respect of the second exemplary embodiment and shown FIG. 2. In the third embodiment, the first Ion exchange step 42 is preceded by a valency réduction step 70. The valency réduction step 70 comprises reducing the valency of ferrie Ions in the WPA12 to produce a valency reduced WPA 72 which is then subjected to first ion exchange step 42. The valency réduction step 70 may be important because any ferrie Iron has a deleterious effect on subséquent process steps of the uranium extraction process. The ion exchange (IX) resin used in subséquent step(s) for the extraction of uranium has a high affinity to load ferrie (Fe³⁺) ions, which Inhibits uranium loading. For this reason, it is préférable for the iron in the WPA feed 12 to be in the ferrous (Fe²⁺) state.

The valency réduction In valency réduction step 70 may be carried out by contacting the WPA containing ferrie (Fe³⁺) ions with a suitable reducing agent. Suitable agents for this purpose include (but are not limited to): metallic Iron; ferro-phosphorus alloy; and ferro-silicon alloy. Altematively, or In addition, the valency réduction In valency réduction step 70 may be carried out by reducing the ferrie (Fe³⁺) Ions in the WPA in an electroreduction step.

In some embodiments, the valency réduction step 70 comprises adding metallic iron to a reactor containing WPA 12 in order to reduce the ferrie Iron to ferrous iron. For example, concentrate may be pumped into three agitated tanks with a total résidence time of three hours. Powdered or granular Iron may be added into the first of two reactors at 120% stoichiometric équivalent (relative to the amount of ferrie iron). Altematively, the metallic Iron could be substituted with or used in combination with ferro-phosphorus alloy or ferro-silicon alloy.

In some embodiments, the valency réduction step 70 comprises electroreduction. Electroreduction may be advantageous because no chemical species are added to the WPA and It is easy to control electrolytic réduction. In one form of the electroreduction stage WPA feed is transferred to continuously operated electroreduction cells.

FIG. 4 Is a flow chart describing a fourth exemplary embodiment of the Invention which is a process 40 for extracting uranium from wet-process phosphoric acid (WPA) 12. Process steps 42, 48, 54, 58, 62, 64 and 70 in this embodiment are the same as those described in respect of the third exemplary embodiment and shown FIG. 3. In the fourth embodiment, the valency réduction step 70 Is preceded by an Iron removal step 74. The iron removal step 74 comprises decreasing the amount of dissolved Iron species in the WPA relative to the amount of uranium species in the WPA to produce a lowered iron content WPA 76 having uranium species therein 76. The lowered iron content WPA 76 has a lower amount of dissolved Iron species than the raw WPA 12. The lowered iron content WPA 76 is then subjected to the valency réduction step 70, which Involves subjecting the lowered Iron content WPA 76 to a réduction step, wherein the valency of dissolved Iron species remaining In the lowered Iron content WPA 76 is reduced.

The aim of the Iran removai stage 74 Is to lower the iron content. This can be done by removing the majority of the total iron présent through précipitation of an Iron ammonium phosphate (IAP) compound from the feed or pretreated WPA. The IAP précipitation step is designed to remove a portion of the ferrie iron, as a partial step prior to the valency réduction step. Additionally IAP précipitation reduces sealing species (fluorosilicate and gypsum) in the lowered iron content WPA 76 prior to an ion exchange step which, in tum, Improves operability of the Ion exchange step.

in the Iron removai step of the exemplary embodiments, WPA is transferred to a small pre-mlx tank ammonia is added at a stoichiometric excess of approximately 300 - 1000% of the calculated ammonia requirements for formation of IAP. From the pre-mix tank, the treated stream is transferred to overflow reactors. The treated stream has a total résidence time of 7 to 12 hours in the overflow reactors to allow completion of the IAP précipitation process. The overflow from the overflow reactor Is transferred to a centrifuge, or other solid liquid séparation device, where IAP is separated from the WPA. The lowered Iron content WPA 76 (low solid concentration) is then transferred to the iron valency réduction step 70.

FIG. 5 is a flow chart describlng a fifth exemplary embodiment of the Invention which Is a process 80 for extracting uranium from wet-process phosphoric acid (WPA) 12. The process 80 comprises an oxidation step 82 In which uranium laden WPA 12 is contacted with an oxidant 84 to provide an oxîdized WPA stream 86. The oxidized WPA stream 86 is then contacted with a solvent 88 comprising di(2-ethyihexyl)phosphoric acid and trioctylphosphine oxide In a solvent extraction step 90. A uranium enriched organic solvent stream 92 Is then separated from a WPA containing aqueous stream 94 and the uranium enriched organic solvent stream 92 is contacted with an ammonium carbonate solution 94 In a stripping step 96 under conditions to provide a uranium enriched ammonium carbonate stream 98. The uranium enriched ammonium carbonate stream 98 is then contacted with an Ion exchange resin in an ion exchange step 100. A uranium depleted ammonium carbonate stream 102 Is separated from the Ion exchange resin and the resin Is contacted with a solution containing chloride Ions 104 and a uranyl solution 106 is separated from the Ion exchange resin.

FIG. 6 is a flow chart describing a sixth exemplary embodiment of the Invention which Is a process 80 for extracting uranium from wet-process phosphoric acid (WPA) 12. Process steps 82, 90, 96 and 100 In this embodiment are the same as those described In respect of the fifth exemplary embodiment and shown FIG. 5. In the sixth embodiment, the solvent extraction step 90 is preceded by an iron removai step 108. The iron removai step 108 comprises lowering the concentration of Iron in the WPA 12 to produce a lowered Iron content WPA 110 that is then subjected to the solvent extraction step 90. The Iran removal step may be carried out as described prevlously.

In any of the exemplary embodiments, the uranium containing product 28 or uranyl solution 106 may be further treated to produce a commercial uranium product. In some embodiments, the uranium may be precipitated from the uranium containing product 28 or uranyl solution 106. The step of precipitatîng the uranium from the uranium containing product 28 or uranyl solution 106 comprises acidification and removal of carbon dioxlde generated, formation of a uranyl peroxide through the addition of hydrogen peroxide, as well as caustic soda as required for maintaining a suitable pH for the précipitation reaction. The step of drying the precipitated product Involves thickening the precipîtate In a high rate thickener and drying in a low température dryer at 260^e C.

The uranium containing product 28 or uranyl solution 106 is pumped into the first of three tanks in sériés. Hydrogen peroxide and caustic soda Is added to enable precipîtate uranium of oxides. The total résidence time in the précipitation reactors is three hours. The underflow is transferred to a thickener, followed by drying of the precipîtate at around 260^e C and subséquent drumming Into drums and finally packaging into shipping containers.

Throughout this spécification the word comprise, or variations such as comprises or comprising, will be understood to Imply the Inclusion of a stated element, integer or step, or group of éléments, integers or steps, but not the exclusion of any other element, integer or step, or group of éléments, integers or steps.

Ali publications mentioned in this spécification are herein incorporated by reference. Any discussion of documents, acts, materials, devices, articles or the like which has been included In the présent spécification Is solely for the purpose of providing a context for the présent invention. It is not to be taken as an admission that any or ail of these matters form part of the prior art base or were common general knowledge in the field relevant to the présent Invention as It existed In Australie or elsewhere before the priority date of each claim of this application.

It will be appreciated by persons skilled in the art that numerous variations and/or modifications may be made to the invention as shown in the spécifie embodiments without departing from the spirit or scope of the invention as broadly described. The présent embodiments are, therefore, to be consldered In ail respects as illustrative and not restrictive.

Many modifications and other embodiments of the invention will corne to the mind of one skilled In the art having the benefit of the teachings presented in the foregoing descriptions and the associated drawings. Therefore, it Is understood that the invention is not to be limited to the spécifie embodiments disclosed, and that modifications and embodiments are intended to be included within the scope of daims supported by this disclosure.

Claims (10)

THAT WHICH IS CLAIMED IS:

1. A process for extracting uranium from wet-process phosphoric acid (WPA), the process comprising:

(a) separating uranium from WPA to produce a loaded uranium solution stream and a uranium depleted WPA stream;

(b) contactîng the loaded uranium solution stream with an ion exchange resin;

(c) eluting uranium species bound to the ion exchange resin by contactîng the resin with a solution comprising anions to produce a loaded uranium eluant stream; and (d) treating the loaded uranium eluant stream to provide a uranium containing product.

2. The process of claim 1, wherein the anions used to elute the uranium species in step (c) are selected from the group consisting of: chloride anions, sulphate anions, nitrate anions, and combinations thereof.

3. The process of claim 1, wherein step (a) is preceded by a valency réduction step comprising reducing the vaiency of ferrie Ions In the WPA.

4. The process of claim 3, wherein step (a) and/or the valency réduction step (if used) is preceded by an iron removal step.

5. The process of claim 1, wherein step (a) is preceded by:

decreasing the amount of dissolved iron species in the WPA relative to the amount of uranium species in the WPA to produce a lowered iron content WPA having uranium species therein; and subjecting the lowered iron content WPA to a réduction step, wherein the valency of dissolved Iron species remaining in the lowered Iron content WPA is reduced.

6. A process for extracting uranium from wet-process phosphoric acid (WPA), the process comprising:

(a) contactîng uranium laden WPA with a first Ion exchange resin to form uranium depleted WPA;

(b) separating the uranium depleted WPA from the first ion exchange resin;

(c) oxidizing uranium spedes on the first Ion exchange resin by contacting the first Ion exchange resin with an oxidant;

(d) contacting the first ion exchange resin with ammonia to remove impurities from the resin, the Impurities being vanadium Ions, organic spedes, or a combination thereof;

(e) separating the impurities from the first Ion exchange resin;

(f) removing the oxidized uranium spedes from the first Ion exchange resin by contacting the resin with ammonium carbonate to form a uranium enriched ammonium carbonate stream;

(g) contacting the uranium enriched ammonium carbonate stream with a second ion exchange resin to form uranium depleted ammonium carbonate;

(h) separating the uranium depleted ammonium carbonate from the second Ion exchange resin; and (i) eluting uranium spedes from the second Ion exchange resin to form a uranyl solution.

7. The process of daim 6, wherein the oxidant Is selected from the group consisting of: air, oxygen, hydrogen peroxide, WPA, and combinations thereof.

8. The process of daim 6, wherein the elution in step (i) is carried out using a solution comprising anions selected from the group consisting of: chloride anions, sulphate anions, nitrate anions, and combinations thereof.

9. The process of claim 6, wherein step (a) Is preceded by a valency réduction step comprising reducing the valency of ferrie ions in the WPA.

10. The process of daim 9, wherein the valency réduction step Is preceded by an iron removal step.

11. The process of claim 6, wherein the uranyl solution is further treated to provide a uranium containing product.

12. The process of daim 11, wherein the further treatment comprises a précipitation step.

13. The process of daim 6, wherein step (a) is preceded by:

decreasing the amount of dissolved iron species In the WPA relative to the amount of uranium spedes In the WPA to produce a lowered Iron content WPA having uranium spedes t herein; and subjecting the lowered iron content WPA to a réduction step, wherein the valency of dissolved Iron spedes remaining in the lowered Iron content WPA is reduced.

14. A process for extracting uranium from wet-process phosphoric add (WPA), the process comprising:

(a) contacting uranium iaden WPA with an oxidant to form an oxidized WPA stream;

tb) contacting the oxidized WPA stream with an organic solvent;

(c) separating a uranium enriched organic solvent stream from an aqueous WPA stream;

(d) contacting the uranium enriched organic solvent stream with an ammonium carbonate stream to form a uranium enriched ammonium carbonate stream;

(e) contacting the uranium enriched ammonium carbonate stream with an ion exchange resin;

( f ) separating a uranium depleted ammonium carbonate stream from the ion exchange resin;

(g) contacting the ion exchange resin with a solution comprising chloride ions; and (h) separating a uranyl solution from the ion exchange resin.

15. The process of daim 14, wherein the organic solvent comprises di(2-ethyihexyl)phosphoric add and triodylphosphlne oxide.

16. The process of daim 14, wherein step (a) Is preceded by an Iron removal step.

17. The process of claim 14, wherein the uranyl solution Is further treated to provide a uranium containing product.

18. C The process of claim 17, wherein the further treatment comprises a précipitation step. D 19. The process of claim 14, wherein step (a) is preceded by: decreaslng the amount of dissolved Iron species in the WPA relative to the amount of

uranium species in the WPA to produce a lowered iron content WPA having uranium species thereln; and

10 subjecting the lowered iron content WPA to a réduction step, wherein the valency of dissolved iron species remalnlng In the lowered iron content WPA is reduced.