Pilot scale optimization of a chromatographic method for purification of Molybdenum-99 (cold and hot tests)

Technicium-99 as a widely used radionuclide in nuclear medicine was obtained from molybdenum-99 which mainly produced by fission of Uranium-235. Separation and purification of molybdenum from other fission products are considered as a big challenge due to its high activity and variety of impurities. In this research, anion exchange chromatography was used for the purification of Mo-99 on a semi-industrial scale as 0.02mg (100mCi). The optimization of the effective parameters including the amount of resin, flow rate and volume of solutions entering the column in each step of washing and rinsing in two modes was performed by two methods; cold test (by addition of Mo- 99 as a tracer to the feed solution) and hot test (using a real sample obtained from acidic dissolution of the irradiated target containing U-235 (U3O8/Alx). The values of the optimum parameters for the cold/hot tests including the amount of resin 4g /7.5g, the eluent volume 50ml/70ml, the washing volume 60ml/84ml and the flow rates of elution step were 5.64ml/min/ 4ml/min, respectively. The loading and Washing speeds were the same for both modes. The Molybdenum purity obtained in the cold test was up to 100% and up to 98.17%.for the hot test.