The ability to concentrate the isotope Ra-224. Ra-224 is a valuable isotope for emerging Pb-212/Bi-212 cancer therapies. Ra-224 is source material that is loaded onto generators and delivered to hospitals where Pb-212 is collected and administered to patients. Furthermore, Ra-224 is also being examined as a material to administer directly to treat some forms of cancers. Such an example includes the embedding of Ra-224 into microspheres that are injected into the peritoneal cavity to treat cancer metastases in this location. The collection of Ra-224 originated from natural thorium as the source material where three separations are utilized to collect Ra-228, Th-228, and Ra-224. Furthermore, this allows the extraction of Th-228 as the deliverable material if it is desired.
DOE is producing Ra-224 to meet demands for early phase research.
The current process: U-238 > Ra-226 > double-neutron-irradiation > Th-228 > ion-exchange chromotography > Ra-224
Separation of Ra-226 from U-238 is a complicated, multi-step process.
AREVA Med has preliminary plans to build a facility to capture Ra-224 from natural Th-232. The AREVA method to recover Ra-224 utilizes several separation steps. The first is a recovery of Ra-228 from a Th-232 nitrate solution by coprecipitating radium by barium sulfate creating a barium-radium sulfate coprecipitate. While the proposed AREVA method does display good selectivity for radium, the specificity is very poor and producing high percentage yields are virtually impossible. The coprecipitation suffers from the low specificity of the reagent and thus requires repeated coprecipitations to even achieve a moderate and suboptimal yield.
No reactor required for production
Single step separations for each stage
Easy to automate (lower exposure)