Study on the Interfacial Corrosion of Carbon Steel in Dilute Hanford Waste Simulants

Corrosion of carbon steel was observed at the liquid/air interface in several dilute waste simulants. These waste simulants typically contains nitrite, nitrate and other chemicals and have pH above 13. Although the nitrate concentrate is high (about 3.7 M), corrosion was not noted on carbon steel being exposed in the bulk solution. Rather, corrosion primarily occurred at the liquid/air interface. This present work aims at understanding the mechanism responsible for the corrosion attack at the interface. Critical experimental parameters that have important impact on the interface corrosion attack will be identified and studied.