Production of molybdenum-99, phosphorus-32, and fluorine-18 using powder recoil methods in a research reactor

The production of radioisotopes has been thought to be limited to nuclear reactors that are ≥1 MW in power. This dissertation describes the use of the powder recoil method, in conjunction with the University of Utah's 100 kW TRIGA nuclear reactor, to attempt to produce high specific activity radioisotopes. To test the feasibility of the powder recoil method, molybdenum-99, phosphorus-32, and fluorine-18 were produced by varying the target materials, and target-to-catcher compound ratios. The admixed target/catcher powders were irradiated for 4 hours or less in two unique in-core facilities. After irradiation, the target/catcher samples were dissolved in a solvent and microfiltered. Subsequent specific activities, yields, and enrichment factors were determined using liquid scintillation or gamma spectroscopy.; While the specific activities of the molybdenum and phosphorus samples were not as high as expected, the enrichment factors (ranging from 0.98 to 20.35 for the molybdenum samples, and 0.40 to 1.41 for the phosphorus samples) indicate that this method will produce a higher enrichment of molybdenum-99 and phosphorus-32 than direct irradiation of pure samples. The fluorine samples had the highest specific activity, and the highest enrichment factors (ranging from 9.26 to 178.85) of the three radioisotopes studied.; These results show that molybdenum-99, phosphorus-32, and fluorine-18 can be produced using this method while decreasing the irradiation time. Furthermore, this standardized technique can be utilized to produce other isotopes of interest including potassium-42, chromium-51, rhenium-186, rhenium-188, and many other reactor produced radioisotopes.