The influence of hydrogen peroxide and hydrogen on the corrosion of simulated spent nuclear fuel
The synergistic influence between H2O2 and H2 on the corrosion of SIMFUEL (simulated spent nuclear fuel) has been studied in solutions with and without added HCO3−/CO32−. The response of the surface to increasing concentrations of added H2O2 was monitored by measuring the corrosion potential in either Ar or Ar/H2-purged solutions. Using X-ray photoelectron spectroscopy it was shown that the extent of surface oxidation (UV + UVI content) was directly related to the corrosion potential. Variations in corrosion potential with time, redox conditions, HCO3−/CO32− concentration, and convective conditions showed that surface oxidation induced by H2O2 could be reversed by reaction with H2, the latter reaction occurring dominantly on the noble metal particles in the SIMFUEL. For sufficiently large H2O2 concentrations, the influence of H2 was overwhelmed and irreversible oxidation of the surface to UVI occurred. Subsequently, corrosion was controlled by the chemical dissolution rate of this UVI layer.
- This article is part of the themed collection: Corrosion Chemistry