Thermal Decomposition of Hydrogen Peroxide and Its Effect on Reactor Water Monitoring of Boiling Water Reactors

The thermal decomposition rate of hydrogen peroxide (H₂O₂) was measured in the aqueous phase at an elevated temperature. It was shown that the reaction follows first-order kinetics, and the rate constant was determined as a function of temperature. The mechanism of the aqueous phase decomposition is discussed, particularly in relation to the activation energy of the reaction. Calculations were carried out for the reactions of O₂, H₂, and H₂O₂ in the boiling water reactor sampling line. It was shown that H₂O₂ disappears, and the back reaction of H₂ and O₂ to water proceeds in the line. This was interpreted on the basis of the radical mechanism of H₂O₂ decomposition.