Optimizing a radiochemical separation of 26Al from an acidic V-rich matrix

During the SINCHRON project, significant amounts of waste were produced, from which valuable radionuclides like (²⁶Al, ^41,45Ca, ⁴⁴Sc/⁴⁴Ti) could be recovered, in addition to the primary radionuclide of interest, ³²Si. For this purpose, 150 vanadium discs (approximately 420 mg each, 99.8% purity, from Goodfellow Cambridge Limited, U.K.) were irradiated for two years in the SINQ (Swiss Spallation Source) Target Irradiation Program (STIP), using the High-Intensity Proton Accelerator (HIPA). After a cooldown period to allow short-lived radionuclides to decay, the V-discs were dissolved and processed for ³²Si. The residual solution was found to contain several exotic radionuclides of interest for recovery as non-carrier added. Among these ²⁶Al was partially separated and processed at ITC, yielding a specific activity of 5–10 Bq/g.

Developing a new and improved ²⁶Al separation process based on a single column adsorption/desorption step would be highly advantageous. The main benefit would be the simplification of the process, as the waste samples are highly active due to ⁶⁰Co, and reduced operating time would minimize radiation exposure. Additionally, avoiding further waste generation and achieving higher specific activities of no-carrier added ²⁶Al would be beneficial for future experiments.

The importance of ²⁶Al spans multiple scientific domains, including radiometric and cosmic ray exposure dating, environmental tracing, and archaeological investigations. Its role in radiotracer studies helps unravel aluminum’s behavior in living organisms and track its movements in various materials. In astrophysics, ²⁶Al aids in understanding nucleosynthesis processes within stars and supernovae. Additionally, in environmental monitoring, it helps resolve terrestrial processes.