A Chemical Approach for the Safety of Lead and Lead/Bismuth Cooled Gen IV Reactors

Research Project, 2019 – 2022

The purpose of the present proposal is to investigate the reactor safety from a chemical point of view for Lead and Lead-Cooled Gen IV Reactors.The physical barriers set up for a safe functioning of a nuclear reactor are (generally): the fuel matrix, the cladding, and the coolant (Lead-Bismuth eutectic or LBE, Pb, other), reactor vessel, primary containment and the secondary containment.The objectives of the present proposal focus on the 3rdphysical barrier (the coolant) capability of retaining and contain the potential fission products (both volatile and non-volatile) release from a damaged fuel pin before leaving the reactor vessel.The aim of the project is to provide sufficient experimental data at an atomistic level for further development of safety systems for Gen IV reactors, in this case cooled with Pb or LBE.The hypothesis to be studied are that the majority of the resulted fission products will be retained and immobilized in the LBE or PB, forming either chemical very stable species through a very fast kinetics or the diffusion and the release of the fission products or their components into a gas phase (e.g. air) is very slow.We will test our formed hypotheses through a combination of empirical measurements and numerical modelling in an interdisciplinary collaboration between nuclear chemistry and environmental inorganic chemistry.