Characterization of the passive properties of 254SMO stainless steel in simulated desulfurized flue gas condensates by electrochemical analysis, XPS and ToF-SIMS

Electrochemical analysis, XPS, and ToF-SIMS are combined to characterize the passive properties of 254SMO stainless steel in the simulated condensates after flue gas desulfurization at different temperatures. Increase in condensate temperature causes the enhanced transpassive dissolution and surface deterioration as well as the involvement of oxygen reduction. Solution deaeration counteracts with the reaction rate acceleration, yielding an invariable donor density from 40 to 60 degrees C. Dissolution and precipitation of Fe and oxidation of Mo are facilitated, resulting in the mixed Cr(III)-Fe(III)-Mo(VI/IV) oxide/hydroxide surface layer and the strengthened enrichment of oxidized Cr and oxidized Mo at high temperatures.