	US 7,578,922 B2
	Method for producing hydrogen by chemical process using heat with electricity
Toshio Nakagiri, Higashi-Ibaraki-gun (Japan)
Assigned to Japan Nuclear Cycle Development Institute, Ibaraki-ken (Japan)
Filed on Sep. 05, 2003, as Appl. No. 10/655,131.
Claims priority of application No. 2003-022580 (JP), filed on Jan. 30, 2003.
Prior Publication US 2005/0077187 A1, Apr. 14, 2005
Int. Cl. C25B 1/00 (2006.01)

U.S. Cl. 205—554 [205/637]

6 Claims

1. A method for producing hydrogen from water which comprises the steps of producing sulfuric acid and hydrogen from water and sulfur dioxide, and decomposing sulfuric acid to produce water, sulfur dioxide and oxygen, reactants in the respective steps being circulated,

wherein said sulfuric acid decomposition comprises a step for vaporizing sulfuric acid to decompose sulfuric acid into sulfur trioxide and water and a step for decomposing sulfur trioxide into sulfur dioxide and oxygen, and

wherein the step for decomposing sulfur trioxide is carried out at a temperature of 600° C. or less by electrolysis using a partition wall of oxygen ion-permeable solid electrolyte and oxygen is separated simultaneously with the electrolysis to thereby produce hydrogen by chemical process, and water using heat with electricity.