Corrosion phenomena of alloys by subcritical and supercritical water oxidation of 2-chlorophenol

Corrosion of Hastelloy C-276, Titanium Gr2, and Zirconium 702 were investigated at subcritical and supercritical conditions using a continuous anticorrosive reactor. The morphology of each alloy surface changed after being exposed by oxidation of 2-chlorophenol in water. The depth of oxygen penetration in the metal exposed by supercritical conditions was generally deeper than that under subcritical conditions. On the other hand, there was a greater loss of alloys at the subcritical condition than at the supercritical condition. Metal oxides and cations from the alloy corrosion in the reactor increased the decomposition efficiency of 2-chlorophenol. The decomposition efficiency from the corrosion of Hastelloy C-276 and Zirconium 702 was slightly higher than that from the corrosion of Titanium Gr2. It can be concluded that Titanium Gr2 has the best corrosion resistance of the tested alloys because it showed the lowest mass loss and oxygen penetration.