Thermochemical water-splittering hydrogen production using nuclear heat

The principle, history and the present state of thermochemical hydrogen production were stated. The method uses water decomposition by chemical reaction cycle to absorb thermal energy at the high temperature and to generate heart at the low temperature. Two thermochemical cycles are studying such as UT (University of Tokyo)-3 process and IS (Iodine-Sulfur) process. UT-3 process uses CaBr2, Fe3O4 and Br2. Test experiment of apparatus (Model Apparatus for Cyclic Operation in Tokyo: MASCOT) succeeded hydrogen and oxygen production. The latter process is studied by JAERI using HTTR (High Temperature Engineering Test Reactor). It is the first case of hydrogen production using the high temperature gas-cooled reactor (HTR). This method uses I2, SO2 and H2SO4. The laboratory test of continuous hydrogen production of IS process showed the stable production velocity of hydrogen and oxygen. Many problems of two methods are explained. (S.Y.)