Sulfide film formation on copper under electrochemical and natural corrosion conditions
2007 (English)In: Corrosion, ISSN 0010-9312, Vol. 63, no 2, 135-144 p.Article in journal (Refereed) Published
The mechanism and kinetics of Cu corrosion in anoxic aque-ous chloride solutions containing sulfide (10–3 mol/L) havebeen investigated electrochemically and under natural corro-sion conditions. Under these conditions Cu is thermodynami-cally unstable in anoxic water, and the anodic growth of achalcocite (Cu2S)/digenite (Cu1.8S) film is supported by thecathodic reduction of water. Electrochemical experiments atrotating disc electrodes and impedance spectroscopy showthat the film growth occurs under SH– transport control asstagnant conditions are approached. At this concentration,film growth can follow two distinct pathways. The initiallyformed film grows rapidly via an ion (or associated defect)transport process. If this film remains coherent, subsequentfilm growth/corrosion is extremely slow. If the developmentof interfacial stresses leads to film fracture, then growthcontinues and a much thicker nodular deposit is formed. Theprimary goal of this research is to develop a mixed potentialmodel, which can be used to assess the performance ofcopper nuclear waste containers in granitic nuclear wasterepositories.
Place, publisher, year, edition, pages
2007. Vol. 63, no 2, 135-144 p.
copper, corrosion potential, electrochemical impedance spectroscopy, high-level waste, mechanism, sulfide, voltrammetry
IdentifiersURN: urn:nbn:se:uu:diva-16952OAI: oai:DiVA.org:uu-16952DiVA: diva2:44723