TECHNOLOGY FOCUS - ELECTRICAL POWER AND ENERGY - Preferred Component: The reformer includes a second pipe (22) inserted into a first pipe (21), an internal space of the second pipe defines a first reacting region (23), and a space between the two pipes defining a second reacting region (27). The second reacting region includes a reforming catalyst (28) for generating hydrogen gas from the fuel through a catalytic reforming reaction. The reforming catalyst generates hydrogen gas from the fuel based on a catalytic reforming reaction, and a water gas shift (WGS) catalyst (29) for reducing a concentration of carbon monoxide (CO) included in the hydrogen gas. The reformer includes a heat transfer unit (33) for transferring the heat energy generated in the first reacting region to the fuel supplied to the second reacting region. The heat transfer unit comprises a first passing member coiling around an external circumferential surface of the first pipe and connected with the first reacting region; and a second passing member coiling around an external circumferential surface of the first pipe to contact the first passing member and connected with the second reacting region.    TECHNOLOGY FOCUS - INORGANIC CHEMISTRY - Preferred Material: The catalyst carrier is an aluminum oxide (Al2O3) carrier. Preferred Composition: Contents of the Pd and Pt catalysts are 0.5-1.5 wt.%, each. A mixing ratio of the Pd catalyst to the Pt catalyst is 99-90:1-10 vol.%. EXAMPLE - The reformer in figure 1 used a catalyst mixture prepared by mixing a palladium (Pd) catalyst supported by an aluminum oxide (Al2O3) carrier and a platinum (Pt) catalyst supported by Al2O3 carrier, for oxidation. The volume ratio of Pt/Al2O3 was 10 vol.% and the volume ratio of the Pd/Al2O3 was 90 vol.%. The supporting quantity of each Pd and Pt was 1 wt.%. The concentration of carbon monoxide (CO) in the reformer and oxidation initiation temperature in the reformer using the oxidation catalyst were 1.5% and room temperature, respectively. The reformer has a little increased CO concentration. The reformer did not require an additional heater, since the oxidation was able to be performed at room temperature. The structure of the reformer was simplified.