Static analysis of the thermochemical hydrogen production IS process for assessment of the operation parameters and the chemical properties

Kasahara, Seiji  ; Onuki, Kaoru; Nomura, Mikihiro*; Nakao, Shinichi*

Sensitivity analysis of the operation parameters and the chemical properties in the thermochemical hydrogen production IS process (iodine-sulfur process) was carried out for a static flow sheet. These parameters were evaluated by hydrogen production thermal efficiency, mass flow rate or heat exchange based on heat/mass balance. The most important parameters were concentration of HI after the electro-electrodialysis (EED) cell and apparent transport number of proton of the cation exchange membrane in the EED cell. HI concentration operation should be operated carefully because the parameters for optimum thermal efficiency and for optimum flow rate and heat exchange were different. For the chemical properties, composition at the inlet of the HI decomposition procedure and HIx pseudo-azeotropic composition had great effects. HI concentration after the EED cell should be optimized for each composition. Order of priority for assessment of the operation parameters and chemical properties was determined by the evaluation.