Production of Lutetium-177 via the Indirect Route Using PUR-1

The use of high flux research reactors, such as the High Flux Isotope Reactor (HFIR), to produce a wide variety of both industrial and medical isotopes has been well documented and proven to be economically feasible. However, due to the lack of access to these high flux facilities by most countries, isotope production methods utilizing reactors with low to moderate flux levels are needed, especially for short lived medical isotopes whose production must be relatively close to the location where they will be administered. In recent years medical isotopes that can both be used for treatment and diagnostic uses have become of great interest. One of the most popular of these theragnostic radionuclides is lutetium-177. Production of high-grade Lu-177 can be achieved in both high and low flux reactors through two different production methods. The current work looks to determine the feasibility of producing Lu-177 via the indirect route, using the relatively low flux of PUR-1. This will be accomplished through the use of high-fidelity models and simulations to predict the resulting production rates of the desired products. The results of these models and simulations will then be compared to the results obtained from the experimental irradiation of various samples of ytterbium oxide in PUR-1. Many studies have successfully produced Lu-177 using moderate and high flux reactors and several papers have studied the predicted production rate for low to moderate flux reactors by using the reported thermal flux of various research reactors and the reported cross-section values for ytterbium. A Monte Carlo based model of PUR-1 will be developed to determine the radiative capture reaction rates for the ytterbium targets across all neutron energies. This model in conjunction with a simplified MATLAB model, to solve the series of partial differential equations describing the production and decay of each product isotope, will be used to predict isotope production rates and will be compared to experimentally obtained results.