Argonne National Laboratory (ANL) is supporting development of accelerator-based production of (sub 99)Mo using the photonuclear reaction (sub 100)Mo(gamma, n)(sub 99)Mo with an enriched (sub 100)Mo target. After dissolution of irradiated Mo target disks in hydrogen peroxide, Mo is converted to potassium molybdate by addition of KOH. The highly alkaline solution of K(sub 2)MoO(sub 4) (0.2 g-Mo/mL in 5 M KOH) is loaded into the TechneGen generator, where Tc is retained on an aqueous biphasic extraction chromatography (ABEC) column, while Mo passes through and is recovered for further processing. After the molybdenum is processed in the TechneGen generator, the spent solution needs to be treated to recover valuable Mo-100 for future production of sintered Mo disks. Therefore, recycle of Mo will require conversion of K(sub 2)MoO(sub 4) in 5 M KOH solution to MoO(sub 3) powder that can be further reduced to Mo metal. The starting Mo-100 enriched material contains 20-40 mg of potassium in one kilogram of molybdenum. However, after dissolving the irradiated Mo-100 target in hydrogen peroxide and converting it to K(sub 2)MoO(sub 4) in 5 M KOH (0.2 g-Mo/mL), the solution contains about 1.8 kg of potassium per kilogram of molybdenum. One requirement for the recycled Mo material is that the impurities in the recycled material be at the same or lower concentration than that present in starting material to facilitate acceptance for use of recycled Mo-100 by the U.S. Food and Drug Administration (FDA). The required purification factor for removal of potassium in purified MoO3 powder is approximately 1 x 10(sub 5), which would prevent production of large amounts of K-42 during the irradiation of Mo-100 disks at the low energy accelerator facility (linac). Additionally, recycle of Mo requires conversion of K(sub 2)MoO(sub 4) in 5 M KOH solution to MoO(sub 3) powder with high Mo recovery yields (>98%) due to a high cost of enriched Mo-100 material.
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