Test fabrication of sulfuric acid decomposer applied for thermochemical hydrogen production IS Process

Noguchi, Hiroki  ; Ota, Hiroyuki*; Terada, Atsuhiko  ; Kubo, Shinji  ; Onuki, Kaoru; Hino, Ryutaro

Thermo-chemical IS process produces large amount of hydrogen effectively. Since the IS process uses strong acids such as sulfuric acid and hydriodic acid, it is necessary to develop large-scale chemical reactors featuring materials that exhibit excellent heat and corrosion resistance. A sulfuric acid decomposer is one of the key components of the IS process. The decomposer is exposed to severe corrosion condition of sulfuric acid boiling flow, where only the SiC ceramics shows good corrosion resistance. However, at the current status, it is very difficult to manufacture the large-scale SiC ceramics structure required in the commercial plant. Therefore, we devised a new concept of the decomposer, which featured a counter flow type heat exchanger consisting of cylindrical blocks made of SiC ceramics. This paper describes results of the design work and the test-fabrication study of the sulfuric acid decomposer, which was carried out in order to confirm its feasibility.