FİGES develops projects to produce Molybdenum-99 (Mo-99) radioisotope, which attracts great demand in the field of nuclear medicine of our country – as it the case in all around the world – and is still being imported. Within the scope of the R&D and feasibility studies performed for building a prototypical reactor, the researchers have focused on various models to develop a Aqueous Homogeneous Reactor classified under the Homogenous Reactors, which can allow the production of the Mo-99 radioisotope.
The “fuel,” which is to invoke a separation reaction in the liquid homogenous reactors, is the “uranyl salt,” composing of maximum 19.75% uranium-235 isotope (enriched uranium). The “liquid solution” prepared with this salt easyly dissolved in water is poured into a spherical or cylindrical container after being prepared in mass capable of self-sustaining the nuclear reactions. The temperature emerging during the nuclear separation reaction must be mitigated out of the setting to prevent the solution temperature from exceeding 90°C.
Aside from Mo-99, other valuable radioisotopes of the nuclear medicine, such as Xe-133, Sr-89, Y-90, I-131, are among the separation products emerging during the separation of the uranium. During the process, a certain amount of uranyl nitrate solution is extracted and involved in the “chemical cleaning” process to ensure continuous separation of these radioisotopes. The figure below demonstrates the chart of ARGUS Solution Reactor which is operated at the Kurchatov Institute in Russia. Until now, 30 Solution Reactors, which go back to as far as 45-50 years, have been manufactured. A wide operational knowledge and data is available regarding the operation of these reactors, whose thermal powers range between 50 kW and 5 MW.
Based on the calculations, the Solution Reactors are positioned to attract interest once again, thanks to their features such as high Mo-99 production efficiency, low cost, small need for “critical mass,” passive security systems, and simplified fuel processes.
International Atomic Energy Agency has also suggested the Solution Reactors as a serious alternative to ensure more efficient use of medical radioisotopes (Mo-99), whose supply has been constrained due to the closure of the expired production reactors around the world, for human health purposes*.
The fact that the manufacturing and design calculations of the Solution Reactors involve codes such as ANSYS is an important driving force for FİGES to assume a leading role in this field.
* IAEA, Production and Supply of Molybdenum-99, Nuclear Technology