Rapid separation of 99Mo from proton irradiated thorium target for medical application

Molybdenum-99 is an important radionuclide used in nuclear medicine, and efficient extraction of high purity 99 Mo from irradiated target is required to meet the medical application demands. A novel method is presented for the separation and purification of 99 Mo from thorium target irradiated by accelerator proton beam. In this method, ThO 2 target was dissolved in mixed HCl and HF acids, and Mo as MoO 2 Cl n− was preliminary separated from the Th matrices and many other radionuclide impurities using anion exchange chromatography. By precipitation of Mo with α-benzoin oxime (ABO) and secondary anion exchange chromatography purification, an overall chemical recovery of consistently over 80% for 99 Mo was achieved. A pure 99 Mo solution matching the requirements for medical purpose (according to European Pharmacopoeias for 99 Mo produced from neutron irradiated 235 U) was obtained with this method, and the produced 99 Mo can be directly used for the preparation of 99 Mo- 99m Tc generator.