Abstract: A method for producing hydrogen gas, is disclosed which is characterized by reacting “mineral ion water containing at least alkaline earth metal ions and having pH of 11 or more to 14 or less” and “mineral-supported high-temperature burned carbonaceous substances made by impregnating mineral ion water in an organism-derived carbon precursor and burning the precursor at high temperature”; a mineral-supported high-temperature burned carbonaceous substance for the above-mentioned method of producing of hydrogen gas; and a method for producing mineral ion water for the above-mentioned method of producing hydrogen gas, wherein the mineral ion water is made by dissolving at least oxide, hydroxide, carbonate, or hydrogencarbonate of magnesium or calcium in water to contain alkaline earth metal ions in the water, adjusting pH of the water, and dissolving a water-soluble component of organism-ash in the water.

Abstract: A method for producing hydrogen gas, is disclosed which is characterized by reacting “mineral ion water containing at least alkaline earth metal ions and having pH of 11 or more to 14 or less” and “mineral-supported high-temperature burned carbonaceous substances made by impregnating mineral ion water in an organism-derived carbon precursor and burning the precursor at high temperature”; a mineral-supported high-temperature burned carbonaceous substance for the above-mentioned method of producing of hydrogen gas; and a method for producing mineral ion water for the above-mentioned method of producing hydrogen gas, wherein the mineral ion water is made by dissolving at least oxide, hydroxide, carbonate, or hydrogencarbonate of magnesium or calcium in water to contain alkaline earth metal ions in the water, adjusting pH of the water, and dissolving a water-soluble component of organism-ash in the water.