Fabrication of Strontium — 90 Vacuum Beta-Voltaic Batteries During SNF Processing by Ion Sputtering – Thermal Separation Technology

This paper is devoted to the extraction of the beta-emitting strontium-90 from spent nuclear fuel (SNF) by the ion sputtering-thermal separation (IS-TS) technology. The IS-TS technology is developed by us for the SNF processing and the selective separation of fission products. Due to theoretical considerations, it can be shown that this technology may be used to extract various useful isotopes from SNF. In particular, strontium - 90, (well-known beta emitter) can be explored via one-step IS-TS process and used to develop new beta-voltaic energy sources. The main idea of IS-TS process is the ion and thermal atomic sputtering of the SNF pellets in the inert gas plasma and these atoms differential condensation with respect to their saturated vapor temperatures downstream of some diffusion tube with inert gas flow. The selective deposition of the required chemical elements (e.g., strontium-90) is carried out in the metallic form on the internal surface of individual removable tubing sections inserted into the diffusion separation tube. Extracted strontium - 90 from prescribed tubing section is used for the fabrication of beta-active layer inside of “nano-micro-sandwich” for the manufacturing of “eternal” energy sources-a new vacuum-beta-cell (VBC).