Hydrogen production and fixation of sulfur from H₂S by reaction with MO_x and M(OH)_x

Hydrogen production and sulfur fixation by the reaction of H₂S was studied by dry process using metal oxides (Mox) and hydroxides M(OH)x. By the thermogravimetry of geocite FeOOH, which was a mixted state of Fe ₂O₃ and Fe(OH)₃, in H₂S atmosphere, it was found that H₂S reacted with FeOOH at low temperature (100-200°C) forming FeS₂ followed by the decompositon of FeS ₂ to FeS at 500°C. Hydrogen was quantitatively produced according to the chemical reaction between H₂S and FeOOH by heating up to 200°C. The hydrogen production reaction could be applicalible to the other metal oxides and hydroxides. In In this case, the divalent sulfur of H ₂S is oxidized to form polysufide, while the hydrogen is reduced to from hydrogen gas. Several types of hydrogen sulfide gases of several concentrations from different types of sulfur resources, such as sour gas, desulfurization of oil, industrial wastes, could be used. Metal hydrooxides produced from metal containing industrial wastes, such as sludge, are also applicable to the present hydrogen production process.