Corrosion in Reducing Environments

Reducing environments involve cathodic reactions generally at or below the proton reduction reaction. Such environments are important in many chemical process and refinery environments. This chapter describes the corrosion behavior of Ni and its alloys in sulfuric, hydrofluoric, hydrochloric, hydrobromic, orthophosphoric, and organic acids. The effect of alloying elements on depassivation pH is described. The corrosion rates in these environments is correlated to alloying elements using empirical and model-based analyses. The corrosion in reducing acid mixtures is discussed.