| Abstract |
| Hydrogen is considered to be an ideal energy source in the foreseeable future. The bulk hydrogen is commercially produced by the catalyzed steam reformation of carbonaceous materials. However, CO_2-gas is producted as a by-product which brings about problems of green house. Therefore, it is necessary to develop a new method which is free from the green house effect and good for the fuel cell. Such a hydrogen can be produced from water by using a variety of energy source, such as solar and nuclear energies without detrimental environmental effects, but known, yet, not to be feasible. It is, however, well known that metals or their lower oxides can effectively reduce steam to produce the high quality hydrogen. In this experiment, iron and its oxide pellets were used as reducers to produce hydrogen gas from steam. Reduction was carried out by passing superheated steam through the pellet-bed in a vertical tube furnace at temperatures of 500 to 900℃ and hydrogen gas produced was measured volumetrically. Results show that the effective reduction of steam was obtained at temperature about 800℃ and the reduction reaction follows the linear rate law. It is also worth to note that wustite was the most active reducer among iron and its higher oxides. The yield was found to be about 56 ㏖e% of hydrogen at the consumption rate of water, 10 ㎖ per hour at 900℃. The reduction mechanism was discussed in terms of the cation deficit structure of wustite. |
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| Key Words |
| Hydrogen production, Steam decomposition, Ferrous iron oxide, Steam-iron process |
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