Abstract: With a method producing hydrogen by making iron or iron oxide contact water, water vapor, or a gas including water vapor, a hydrogen generating medium, which has a high hydrogen generation reaction rate and is resistant to a repetition of oxidation-reduction without degrading its activity, is provided by adding a different metal (such as Ti, Zr, V, Nb, Cr, Mo, Al, Ga, Mg, Sc, Ni, Cu, etc.) other than the iron to the iron or the iron oxide.

Abstract: A method for reducing a metal oxide and a method for manufacturing hydrogen are provided for easily reducing an oxide of a metal that decomposes water to generate hydrogen, using a gas that includes hydrocarbons, such as municipal gas. The method for reducing the metal oxide includes the step of reducing, using a reducing gas that includes hydrocarbons, a medium comprising an oxide of a metal that decomposes water to generate hydrogen, and at least one metal selected from the group consisting of platinum group elements, copper, nickel and cobalt. Furthermore, the method for manufacturing hydrogen includes the above-described reducing step, and a water-decomposing step of reacting water with the medium that is reduced in the reducing step, to generate hydrogen.

Abstract: A method for producing hydrogen by contacting water, steam or gas containing steam with iron or iron oxide, wherein the iron or iron oxide is added with at least one metal of Rh, Ir, Ru, Pd, Pt and Os and at least one metal of Ti, Zr, V, Nb, Cr, Mo, Al, Ga, Mg, Sc, Ni and Cu. The method provides a medium for producing hydrogen which is capable of producing hydrogen at relatively low temperature and at a great generation rate, is free from the decrease of activity, and is resistance to repeated oxidation and reduction, which leads to the decomposition of water and production of hydrogen with good efficiency.

Abstract: Provided is a method of and an apparatus for decomposing hydrogen. The method includes the steps of introducing hydrocarbons into a reaction vessel in a closed-loop system, at least partially decomposing the hydrocarbons into hydrogen by heating the hydrocarbons in the reaction vessel in the presence of a catalyst, introducing the hydrogen into a cassette with metal oxide contained therein, reducing the metal oxide in the cassette to metal or metal oxide having a lower valence by at least partially reacting the metal oxide with the hydrogen to form water, and returning unreacted hydrogen to the reaction vessel. Also provided is a method for producing hydrogen for an apparatus in need thereof.

Abstract: With a method producing hydrogen by making iron or iron oxide contact water, water vapor, or a gas including water vapor, a hydrogen generating medium, which has a high hydrogen generation reaction rate and is resistant to a repetition of oxidation-reduction without degrading its activity, is provided by adding a different metal (such as Ti, Zr, V, Nb, Cr, Mo, Al, Ga, Mg, Sc, Ni, Cu, etc.) other than the iron to the iron or the iron oxide.

Abstract: Object is to construct a system wherein hydrogen is produced from hydrocarbons such as methane or natural gas that has methane using catalyst without emission of carbon dioxide and is used to reduce metal oxide, and hydrogen can be supplied by reaction between the reduce metal oxide and water, and hydrogen can be repeatedly generated by means of metal oxide of cassette type.