Studies on production of high specific activity 99Mo and 90Y by Szilard Chalmers reaction

Abstract

Abstract Attempts have been made to use Szilard Chalmers reaction to prepare 99Mo and 90Y in high specific activity. Experiments were carried out using irradiation of freshly prepared oxinate complexes of molybdenum and yttrium in the HOR reactor of Reactor Institute at TU Delft. The irradiated target was dissolved in dichloromethane and the radionuclides were separated by solvent extraction into aqueous phase. Detailed investigations on the effect of pH of aqueous solution, irradiation time and target amount was also carried out to optimize the enrichment factor and yield. The highest enrichment factor for 99Mo was found to be around 200 with a yield close to 30%. In the case of 90Y, solvent extraction method did not yield high enrichment factors. Slightly higher enrichment factors were achieved with ion exchange method. Studies were also carried out with yttrium oxide nano-powder. Speciation study of 99Mo in the separated aqueous fraction showed it to be present as 99MoO4 2− ion. The results appear to be quite promising for large scale production of 99Mo for medical applications.