EVALUATION OF CONTAINER USING HYBRID TECHNIQUE FOR THERMOCHEMICAL WATER-SPLITTING IODINE-SULFUR PROCESS

Abstract

Hydrogen is one of the promising major energy sources in the future. A thermochemical water-splitting iodine-sulfur process (IS process) is one of candidates for the large-scale production of hydrogen using heat from nuclear energy or solar power. Severe corrosive environment which is thermal decomposition of sulfuric acid exists in the IS process. To achieve an industrialization of massive hydrogen production system, one of the key factors is the development of structural materials for the severe corrosive environment. A hybrid material with corrosion-resistance and ductility was made by a silicon powder plasma spraying and laser treatment. To confirm the production characteristics of a container using the hybrid material, the container which has a welded part, a chamfer, a curved surface was experimentally made. The substrate of the container made of Hastelloy C276 superalloy includes TIG welded part. A corrosion test of the container was performed in 95 mass% boiling sulfuric acid until 500 hours to evaluate the corrosion characteristic of the container. The container had excellent corrosion resistance in the condition of 95 mass% boiling sulfuric acid.