Published April 1999 | Version v1
Journal article

Corrosion mechanism of stainless steel in nitric acid solutions containing ruthenium compounds

  • 1. Hitachi Research Laboratory, Hitachi, Ltd., Ibaraki (Japan)

Description

The effect of ruthenium on corrosion of stainless steel in nitric acid solutions ws evaluated through immersion test, electrochemical measurement, quantitative analysis of RuO4 or NOx and corrosion test under gamma-irradiation. Under non-irradiation, Ru3+ or RuNO3+ was oxidized to RuO4 in concentrated nitric acid solutions at high temperature, and the corrosion of stainless steel was promoted first through by the reduction of RuO4 to a lower valent state compound like RuO2. If the reduction product of RuO2 was deposited on stainless steel , then the corrosion was further promoted through a catalytic function of the deposit for a reduction of nitric acid to HNO2. It was found that the promotion of corrosion with ruthenium was extremely reduced by gamma-irradiation (1 x 106 R/h), due to inhibition of the oxidation of RuO4 from Ru3+ or RuNO3+ by formation of nitrous acid resulting from radiolysis of nitric acid solution. (author)

Additional details

Publishing Information

Journal Title
Zairyo To Kankyo
Journal Volume
48
Journal Issue
4
Journal Page Range
p. 235-241
ISSN
0917-0480