Optimization of the rate of production 99Mo-99mTC through fission in the TRR

Technetium is one of the most important radioisotopes recognized in medicine which is obtained through ‎the decay of molybdenum 99.The half-life of this radioisotope is 6 hours and it is capable of 140 kev gamma ray emission. Due to its short half-life, this radioisotope must be produced at the site of consumption, so that the shortest possible time interval between production and consumption can be achieved. The aim of the present study was the neutronic ‎evaluation of the amount ‎of 99Mo-99TC production through nuclear fission in the Tehran research reactor. The primary core ‎of the reactor with the code MCNP X 2.6 was simulated and neutron flux was assessed in 6 locations. ‎Then, the fuel plate was placed at the site with the highest neutron flux. In different phases, changes ‎were made in the enrichment of fuel. Moreover, the amount of molybdenum produced in each phase was ‎calculated. Based on the results, the amount of‎ molybdenum produced, and thus,‎ the amount of ‎technetium were the highest in the 20% enriched fuel.