Analysis of Corrosion Products Formed on Copper in Cl2 /  H 2 S  /  NO 2 Exposure

Abstract

A joint effort has been undertaken, involving four laboratories and nine different analytical techniques, aiming at characterizing corrosion products on copper formed in mixed flowing gas test containing , , and . The results and considerations clearly show that the identification of different crystalline or noncrystalline phases in the corrosion products only can be performed by a combination of independently working analytical techniques. Cuprite, , is the dominating phase during initial exposure, whereas cuprite together with atacamite, , are the most abundant phases after 10 days of exposure. In addition, the corrosion products contain minor amounts of sulfide, , sulfate, most likely as posjnakite, , and nitrate, most likely as gerhardite, . A nonstoichiometric cuprous oxide, , has also been detected by several techniques.