TECHNOLOGY FOCUS - INORGANIC CHEMISTRY - Preferred Oxide: The oxide is gamma-alumina, zirconia, titania, and/or niobium pentoxide.    TECHNOLOGY FOCUS - MECHANICAL ENGINEERING - Preferred Components: The hydrogen-production apparatus has a heat supply system (21) in which reaction heat supply or electricity supply to the catalyst is possible, and metal heat exchanger tubes or electric heaters. The heat exchanger tubes or electric heaters are arranged so that the heat supply system contacts the circumference, upper surface, lower surface, and/or inside of the catalyst. The catalyst is divided into two or more units, and each unit is provided with heat supply system.    TECHNOLOGY FOCUS - METALLURGY - Preferred Support: The metallic catalyst supports are metal honey-comb, foam metal, sintered metal, and/or metal cloth.    TECHNOLOGY FOCUS - ORGANIC CHEMISTRY - Preferred Isomer: The isomer is a cis-trans-isomer component. EXAMPLE - As a dehydrogenation catalyst a metal honey-comb support of Fe-Cr-Al type-alloy loaded with Pt and (gamma)-Al2O3 group oxide was used.    The sheath thermocouple was attached to the position based on axial directions from the outer periphery of the catalyst to about 2 mm inside, and temperature measured with this thermocouple was made into reaction temperature.    The straight tube of internal diameter 9.4 mm is prepared as a dehydrogenation device. The electric furnace whose internal diameter of a furnace core tube is 12 mm is prepared for the circumference of the reactor. Reaction heat was supplied by the heat tracing.    The tank of decalin (1:1 mixtures of a trans-isomer and a cis-isomer) which is a raw material of dehydrogenation, the raw-material-supplies pump, the condensation separation apparatus of the dehydrogenation product, etc. were connected to the reactor. Supply speed of decalin shall be 0.075 mL/min.    An electric-furnace output is controlled so that the reaction temperature is 380degreesC. When the dehydrogenation of decalin at a pressure of 3 Mpa is conducted, it is 60% of a decalin conversion ratio. Reaction advanced to 72% of the equilibrium conversion (83 %) in these reaction conditions.    The carbon atom income and expenditure and hydrogen atom income and expenditure before and after the dehydrogenation in this experiment respectively correspond well with 98 % and 101 %. It turned out that the hydrogen gas which corresponds to a decalin conversion ratio was generated. In addition, ratio of the trans-isomer in unreacted decalin after a condensation separation apparatus and a cis-isomer is 1.2:1,    It was clear that only a cis-isomer with quick dehydrogenation speed did not necessarily selectively react, and isomerization reaction from a trans-isomer to a cis-isomer advanced by the reaction system inside.