Role of Chemistry in Analysis on the Leakage Incident of Sodium from the Fast Breeder Reactor of “Monjyu”

Abstract

The chemical reactions of Na-Fe-O₂-H₂O system and their equilibrium constants (600∼1200 K) were expressed in terms of standard equilibrium O₂ pressure P⁰ and standard potential E⁰. The results were graphically illustrated on the equilibrium daiagrams of log P_(O2)(O₂ partial pressure) vs. log(Na₂O)(basicity) or E(potential) vs. log(O²⁻)(basicity). These daiagrams visually and comprehensively show the equilibrium relations in the reactions among molten Na with O₂, H₂O and Fe with their reaction products and give a useful information for analysis of the leakage incident of sodium from the fast breeder reactor of “Monjyu”.