Materials compatibility was examined for the sulfuric acid processing environments in the iodine-sulfur water spitting process. The testing environments were (1) boiling conditions of 40/70/98wt% sulfuric add in the presence of iodine and hydriodic acid, and (2) gaseous mixtures of H2O-SO3 and of H2O-SO3-SO2-O2 at 850℃ .In the former enviromnents, Ta and Zr showed corrosion resistance for the boiling 40/70wt% sulfuric acids, and cast iron with 15%Si did for the boiling 98wt% sulfuric acid. For the latter environment, many high temperature alloys such as Incoloy 800, Hastelloy XR, NSC1 were found to have corrosion resistance.
