Reactor studies of tritium release from lead-lithium eutectic Li15.7Pb with deuterium over the sample

Abstract

At the moment, the lead–lithium eutectic was chosen as a breeding blankets material for a DEMO-type fusion reactor. During the reactor operation radioactive tritium will be produced in the blanket, but the interaction parameters of hydrogen isotopes with lead–lithium eutectic are poorly studied. The most significant processes affecting the release of tritium from the lead–lithium eutectic is its interaction with lithium atoms, as a result of which lithium tritide is formed.The main published studies of eutectics were usually carried out with the samples containing 17% of lithium, but even a small deviation in the lithium–lead concentration will lead to significant changes in the properties of the eutectic with respect to hydrogen isotopes. That is why there is an urgent need to research the generation and release of tritium from a lead–lithium eutectic with a lithium content of 15.7% directly under neutron irradiation.This paper presents the results of experimental studies of the lead–lithium eutectic with 15.7% Li content under neutron irradiation. The investigations were carried out at the IVG1.M research reactor (Kurchatov, Kazakhstan) at thermal power of 6 MW (thermal neutron flux ~1014 n/(cm2·s)). The experiments consisted in following: the deuterium flux (~10−9 mole/s) was supplied into the experimental ampoule with eutectic under irradiation and the release of DT-molecules was registered under various sample’s temperatures. The obtained experimental data allowed us to estimate the parameters of tritium release from Li15.7Pb.

Keywords

• Tritium
• Deuterium
• Lead–lithium eutectic
• Reactor irradiation
• Gas release
• Li15.7Pb eutectic