51313-02155-Cathodic Polarization Properties of Hydrogen Peroxide & Effect on Electrochemical Corr. Potential

Available for download

Product Number: 51313-02155-SG

ISBN: 02155 2013 CP

Author: Masahiko Tachibana

Publication Date: 2013

Member Price: $0.00

Non Member Price: $20.00

Price: $20.00

Qty:

Hydrogen peroxide (H2O2) is the most important oxidant to determine the corrosive environment of boiling water reactors (BWRs). Since H2O2 is unstable at high temperature and electrochemical measurement in high purity water is difficult H2O2 polarization characteristics in the BWR environment are not well known especially at less than 10ppb. Cathodic polarization curves of the H2O2 reduction reaction were measured in simulated BWR conditions at 553K over the H2O2 concentration range of 1 to 1000ppb. The polytetrafluoroethylene chamber was set in a circulating autoclave to reduce decomposition of H2O2 and the potential step method developed for measurements under the BWR conditions was used to measure H2O2 polarization curves. The exchange current density of H2O2 (0.28?A?cm^-2) was more than tenfold higher than that of O2(1.5x10-5?A?cm^-2) at 10ppb. And the Tafel constant (bc) of H2O2 (0.006) was 1/4 lower than that of O2 (0.026). The results indicated that the H2O2 reduction reaction occurs faster than that of O2. The electrochemical corrosion potentials (ECPs) in the H2O2 environment were calculated using obtained polarization curves. The ECPs increased to ca.0Vvs.SHE even at 10ppb and were in good agreement with the ECPs measured by an electrometer. The obtained polarization curves of H2O2 are applicable to calculation of ECPs.