Interactions between molten Flibe and metallic Be

To understand the interactions between molten Flibe and Be, a metallic Be rod was immersed in molten Flibe at 803 K under He atmosphere for 210 h. The Be rod was significantly eroded during immersion in molten Flibe, and the Flibe changed from a clear crystal to a brownish-gray marble-like appearance. The concentration of Be0 in Flibe was evaluated by dissolving salt samples in acid solutions. This dissolution test is based on the reaction of Be0 with proton ions in the acid solutions to generate H2. Hydrogen gas was generated from Flibe contacted with Be under flowing He. The amounts of gas generated corresponded to mole fractions of [Be0]/[Flibe] ranging from 9.9 × 10−4 to 7.6 × 10−3. On the other hand, no H2 was generated from Flibe that was not exposed to Be or which was exposed to Be and then given significant H2–HF–He bubbling. These observations showed that Be does, indeed, dissolve in Flibe as Be0. The fact that no Be0 was detected after bubbling H2–HF–He into the salt indicates that Be0 is an effective redox agent for reacting HF.