Gaseous and volatile fission product release from molten salt nuclear fuel

Molten salt nuclear fuel can be used in reactors simply by replacing the solid fuel pellets in conventional fuel assemblies with molten salts. One issue with this approach is the fate of gaseous fission products. If the tubes are sealed then the pressure will build up (as happens in metallic fuels). Chemical thermodynamic calculations have been carried out on the nature of the volatile species released and show that, providing fuel salt redox potential is properly controlled, only relatively radiochemically benign isotopes are volatile. Gases can therefore be simply vented from the fuel tubes into the coolant avoiding pressure increases.(author)