Processing and evaluation of linear accelerator-produced 99Mo/99mTc in Canada

We are developing electron linear accelerator Mo-100(gamma,n)Mo-99 technology as a replacement to nuclear reactor U-235(n,f)Mo-99 production. We report irradiation of natural molybdenum disks (25 MeV, 10 kW) and Mo-100-enriched disks (35 MeV, 2 kW), their dissolution and the extraction of Tc-99m-pertechnetate. Up to 6.2 GBq Mo-99 was produced, solvent extraction was performed at > 90 % yields of Tc-99m, and quality control showed that a product with high radionuclidic and radiochemical purity could be obtained. Irradiated natural molybdenum products showed more impurities (Nb-91m, Nb-92m, Nb-95m and Nb-95) than enriched target material. Linear accelerator technology is feasible for production of quality Mo-99/Tc-99m, particularly when paired with Mo-100-enriched targets.