TECHNOLOGY FOCUS - ORGANIC CHEMISTRY - Preferred Units: The ethanol modifier has ethylene production portion equipped with ethanol dehydration catalyst, and ethylene modification catalyst positioned at the downstream of the ethylene production portion, and has ethylene modification portion. The ethanol modifier further has a supply portion for supplying water or oxygen-containing gas to ethylene reforming portion. The ethanol modifier has a control portion for controlling supply amount of water or oxygen-containing gas according to catalyst temperature of supply amount of ethanol, ethanol dehydration catalyst, or ethylene modification catalyst or temperature of the outlet gas of ethylene modification portion.Preferred Method: Ethanol is contacted with ethanol dehydration catalyst to produce ethylene. A mixture of ethylene, water or oxygen-containing gas is produced by mixing with ethylene, water or oxygen-containing gas. The mixture is contacted with ethylene modification catalyst to produce hydrogen.    TECHNOLOGY FOCUS - INORGANIC CHEMISTRY - Preferred Composition: The ethanol dehydration catalyst contains compound(s) chosen from aluminum oxide, silicon oxide, zirconium oxide, cerium oxide, cobalt oxide, silica-alumina and zeolite. The ethylene modification catalyst contains element(s) chosen from rhodium, platinum, ruthenium, palladium, rhenium, nickel and cobalt. EXAMPLE - Ethanol of 99.5% purity was modified using rhodium catalyst as ethylene modification catalyst, and silica-alumina catalyst as ethanol dehydration catalyst. Modification condition was adjusted by adjusting the inlet gas temperature of ethylene production portion to 300degreesC. Water/ethanol was supplied at a molar ratio of 3, and oxygen/ethanol was supplied at a molar ratio of 0.6. After modification, the outlet gas of ethylene modification portion was extracted as a sample. The sample had hydrogen content of 33.6%, methane content of 7.5%, carbon monoxide content of 1.8% and carbon dioxide content of 21.1%.