Mitigating or preventing corrosion of metal may be achieved in systems that are alkaline, such as carbon dioxide capture systems. The method may include adding an additive to a system wherein the system is at an alkaline pH; the system has both O2 and CO2 present; or the system is at an alkaline pH and has both O2 and CO2 present. The additive may be selected from the group consisting of: quaternary aromatic amines; quaternary alkyl substituted aromatic amines; and combinations thereof. The corrosion inhibiting properties of the additives may be increased by use of synergistic combinants. The abstract is submitted with the understanding that it will not be used to interpret or limit the scope or meaning of the claims.