Patent Number: 
Section: claims

1. A process for recycling uranium that has been used for the production of molybdenum-99 (Mo-99), comprising:providing an aqueous solution comprising a first nitric acid concentration and a first uranium concentration;irradiating the aqueous solution to produce soluble fission products comprising Mo-99;adjusting the first uranium concentration to a second uranium concentration suitable for formation of uranyl nitrate hydrate crystals;adding an inorganic oxidant to the aqueous solution to ensure that the Mo-99 is in a +VI oxidation state;inducing the formation of uranyl nitrate hydrate crystals and a supernatant; andseparating the uranyl nitrate hydrate crystals from the supernatant. 2. The process of claim 1, wherein the uranium is low enriched uranium. 3. The process of claim 1, wherein the inducing the formation of uranyl nitrate hydrate crystals comprises cooling the aqueous solution to a temperature effective for the formation of the uranyl nitrate hydrate crystals. 4. The process of claim 1, wherein the inducing formation of uranyl nitrate hydrate crystals comprises evaporating the aqueous solution under reduced pressure. 5. The process of claim 1, further comprising separating the Mo-99 from the supernatant after separating the uranyl nitrate hydrate crystals from the supernatant. 6. The process of claim 1, further comprising purifying the uranyl nitrate hydrate crystals after separating the uranyl nitrate hydrate crystals from the supernatant. 7. A process for recycling uranium that has been used for the production of Mo-99, comprising:providing an aqueous solution comprising a nitric acid concentration of about 0.01 M to about 0.5 M, and a uranium concentration of about 80 to 310 gU/L;irradiating the aqueous solution to produce soluble fission products comprising Mo-99;adjusting the nitric acid concentration to about 4 M to about 8 M and the uranium concentration to about 350 to 650 gU/L;adding an inorganic oxidant to the aqueous solution to ensure that the Mo-99 is in a +VI oxidation state;inducing formation of uranyl nitrate hydrate crystals and a supernatant; andseparating the uranyl nitrate hydrate crystals from the supernatant, the supernatant comprising the soluble fission products. 8. The process of claim 7, wherein the uranium is low enriched uranium. 9. The process of claim 7, wherein the inducing the formation of uranyl nitrate hydrate crystals comprises cooling the aqueous solution to a temperature effective for the formation of the uranyl nitrate hydrate crystals. 10. The process of claim 7, wherein the inducing formation of uranyl nitrate hydrate crystals comprises evaporating the aqueous solution under reduced pressure. 11. The process of claim 7, further comprising separating the Mo-99 from the supernatant after separating the uranyl nitrate hydrate crystals from the supernatant. 12. The process of claim 7, further comprising purifying the uranyl nitrate hydrate crystals after separating the uranyl nitrate hydrate crystals from the supernatant. 13. The process of claim 7, further comprising:preparing a second aqueous solution from the uranyl nitrate hydrate crystals, the second aqueous solution comprising a second nitric acid concentration of about 0.01 M to about 0.5 M, and a second uranium concentration of about 80 to 310 gU/L;irradiating the second aqueous solution to produce soluble fission products comprising Mo-99;adjusting the second nitric acid concentration to about 4 M to about 8 M, and the second uranium concentration to about 350 to 650 gU/L;inducing formation of a second batch of uranyl nitrate hydrate crystals and a second supernatant from the second aqueous solution, the second supernatant comprising soluble fission products comprising Mo-99; andseparating the second batch of uranyl nitrate hydrate crystals from the second supernatant. 14. The process of claim 13, further comprising separating Mo-99 from the second supernatant. 15. A process for recycling uranium that has been used for the production of Mo-99, comprising:irradiating a solid target comprising uranium to produce fission products comprising Mo-99;forming an aqueous acidic solution from the solid target, the aqueous acidic solution comprising a uranium concentration and a nitric acid concentration;adjusting the nitric acid concentration to about 4 M to about 8 M, and the uranium concentration to about 350 to 650 gU/L;inducing formation of uranyl nitrate hydrate crystals and a supernatant;adding an inorganic oxidant to the supernatant to ensure that the Mo-99 is in a +VI oxidation state; andseparating the uranyl nitrate hydrate crystals from the supernatant. 16. The process of claim 15, wherein the uranium is low enriched uranium. 17. The process of claim 15, wherein the inducing formation of uranyl nitrate hydrate crystals comprises cooling the aqueous acidic solution to a temperature effective for formation of the uranyl nitrate hydrate crystals. 18. The process of claim 15, wherein the inducing formation of uranyl nitrate hydrate crystals comprises evaporating the aqueous acidic solution under reduced pressure. 19. The process of claim 15, further comprising separating Mo-99 from the supernatant after separating the uranyl nitrate hydrate crystals from the supernatant. 20. The process of claim 15, further comprising purifying the uranyl nitrate hydrate crystals after separating the uranyl nitrate hydrate crystals from the supernatant.