TECHNOLOGY FOCUS - INORGANIC CHEMISTRY - Preferred Process: The electric power generated by the generator is converted into direct current, and electrical potential difference is provided to the stabilized-zirconia film or the proton conductive-material film. The recovered heat is used for endothermic reaction in halogenated hydrocracking unit or sulfuric-acid decomposition unit. Oxygen is produced by the oxygen electrolytic-parting unit. Electrical potential difference is provided to the stabilized-zirconia film or the proton conductive-material film by the electric power generator in the fuel cell. The heat generated from sulfuric-acid concentration unit and hydrohalide concentration unit is supplied to a combustor which performs combustion of oxygen which is not utilize by the fuel cell, and generates hydrogen.    TECHNOLOGY FOCUS - MECHANICAL ENGINEERING - Preferred Apparatuses: The oxygen electrolytic-parting unit has a stabilized-zirconia film which permeates oxygen by electrical potential difference as the oxygen-permeating electrolyte film. The halogen-recycling unit is hydrogen membrane-separation device which separates hydrogen gas by applying voltage difference to proton conductive-material film as the hydrogen permeable film. The halogen-recycling unit has vanadium alloy film or palladium alloy film which permeates hydrogen gas by atmospheric pressure difference as the hydrogen permeable film. The hydrogen-production apparatus has a heat exchanger which recovers exhaust heat from units such as sulfuric-acid concentration unit and hydrohalide concentration unit. A gas turbine (G1) is rotated by the exhaust heat recovered by the heat exchanger, and generates electric power with a generator (I). Another gas turbine (G2) is rotated by the exhaust heat recovered by the heat exchanger, and another generator (II) is made to generate electric power. A fuel cell generates electric power using hydrogen produced by the halogen recycling unit. The hydrohalide concentration unit contains iron oxide as a catalyst, and concentrated hydrogen bromide which is decomposed into bromine and hydrogen.    TECHNOLOGY FOCUS - ORGANIC CHEMISTRY - Preferred Process: The electric power generated by the generator is converted into direct current, and electrical potential difference is provided to the stabilized-zirconia film or the proton conductive-material film. The recovered heat is used for endothermic reaction in halogenated hydrocracking unit or sulfuric-acid decomposition unit. Oxygen is produced by the oxygen electrolytic-parting unit. Electrical potential difference is provided to the stabilized-zirconia film or the proton conductive-material film by the electric power generator in the fuel cell. The heat generated from sulfuric-acid concentration unit and hydrohalide concentration unit is supplied to a combustor which performs combustion of oxygen which is not utilize by the fuel cell, and generates hydrogen.