Patent Number: 055966110
Section: claims

1. A method of collecting a medical isotope from a fission product produced in a nuclear reactor, the method comprising: providing a reactor having a 100 to 300 kilowatt rating;  using a uranyl nitrate solution as a homogeneous fissionable material in the reactor, the fissionable material producing fission products including Molybdenum-99 in the uranyl nitrate solution;  passing a portion of the uranyl nitrate solution from the reactor to and through a column of alumina for fixing the fission products including Molybdenum-99 to alumina in the column;  adding acid to the portion of the uranyl nitrate solution to achieve a pH of about 2 to about 5;  passing the portion of the uranyl nitrate solution at pH of about 2 to about 5, back into the reactor;  removing the fixed fission products from the alumina column through elution with a hydroxide; and  precipitating the resulting elutriant with alpha-benzoinoxime for collecting the Molybdenum-99 as the medical isotope.  a vessel containing a selected quantity of uranyl nitrate solution as a homogeneous fissionable material for producing fission products including Molybdenum-99 in the uranyl nitrate solution at a 100 to 300 kilowatt power rating;  at least one alumina column, the fission products including Molybdenum-99 being fixable to alumina in the column;  means for directing a portion of the solution through the alumina column and thereafter back to the vessel;  means for adding acid to the portion of the solution before it is returned to the vessel and between the column and the vessel;  means for supplying a hydroxide through the column for eluting the fission products fixed to the alumina;  means for receiving the eluted fission products; and  means for precipitating Molybdenum-99 from the fission products using alpha-benzoinoxime in the means for receiving the eluted fission products. 2. The method according to claim 1, wherein the uranyl nitrate solution is passed through the column of alumina for a period of time ranging from approximately 12 to 36 hours. 3. The method according to claim 1, wherein the solution contains U-235. 4. The method according to claim 1, wherein for about 20 liters of uranyl nitrate solution are in the reactor, the portion of the uranyl nitrate solution passing from the reactor being about 0.1 to 1.0 ml/per second. 5. The method according to claim 1, including washing the resulting elutriant with water before collecting the Molybdenum-99. 6. The method according to claim 1, wherein the hydroxide comprises one of sodium hydroxide and ammonium hydroxide. 7. The method according to claim 1, wherein for 20 liters of solution, the solution contains approximately 1,000 grams of U-235 in a 93% enriched uranium. 8. The method according to claim 1, wherein for 100 liters of solution, the solution contains about 2,300 grams of 20% enriched uranium-235. 9. The method according to claim 1, including passively cooling the reactor. 10. A system for collecting a medical isotope from a fission product produced in a nuclear reactor, comprising: 11. A system according to claim 10, including means for passively cooling the vessel. 12. A system according to claim 10, including means for washing the column. 13. A system according to claim 10, including an additional column and valve means connected to the first mentioned and additional column for supplying a stream of solution through only one of the columns at a time. 14. A system according to claim 10, wherein the vessel includes outwardly extending fins, the system including means for cooling the vessel comprising a pool of coolant fluid in which the vessel is immersed. 15. A system according to claim 10, wherein the selected amount of solution comprises 20 liters of solution, the solution containing approximately 1,000 grams of 93% enriched U-235. 16. A system according to claim 10, wherein the selected amount of solution comprises 100 liters containing about 1,000 grams of 20% enriched U-235.