abstract |
Methods and compositions for controlling corrosion of high strength steels in the presence of a cleaning solution for removing iron oxide scale from metal surfaces. A benzotriazole or benzimidazole compound is added to a combination of ethoxylated mercaptan and/or oxidized ethoxylated mercaptan and 1-hydroxyethylidene-1,1-diphosphonic acid. The composition is added to an aqueous system, such as a steam generating system, to remove scale from the metal surfaces. |