NOVELTY - A hydrogen gas is produced by a supercritical hydrothermal process comprising contacting an aqueous solution of methanol at at least 650degreesC and above 22.1 MPa in the presence of a metal surface comprising a heat-resistant nickel alloy, and separating the hydrogen from carbon monoxide, carbon dioxide and the methane at a glassy polymer interface.    USE - For producing hydrogen gas for hydrogen fuel cells.    ADVANTAGE - The method efficiently produced hydrogen while reducing the production of carbon monoxide in the hydrogen off-gas. It utilizes a device that avoids processing difficulties caused by depositing a catalyst in sub-millimeter sized channels by utilizing nickel containing alloy surfaces that act as catalytic reaction sites.    DETAILED DESCRIPTION - Production of hydrogen gas by a supercritical hydrothermal process comprising contacting an aqueous solution of methanol at at least 650degreesC and above 22.1 MPa in the presence of a metal surface comprising a heat-resistant nickel alloy for at least 10 seconds, where the nickel alloy comprises at least 58 wt.% nickel, and 14 wt.% chromium to produce a mixture of off-gases consisting of hydrogen, carbon monoxide, carbon dioxide or methane. The off-gases are cooled, and the hydrogen is separated from carbon monoxide, carbon dioxide, and the methane at a glassy polymer interface.    An INDEPENDENT CLAIM is also included for a device for providing hydrogen gas, comprising:    (1) a reaction chamber comprising helically formed metal tube, inlet and outlet, and interior metal surface, where the metal tube comprises a metal alloy comprising at least 58 wt.% nickel, and at least 14 wt.% chromium;    (2) mechanism for moving an aqueous methanol solution into the inlet and through the reaction chamber;    (3) mechanism for restricting a flow of reaction products exiting through the outlet;    (4) mechanism for heating the aqueous methanol solution in the reaction chamber to 650degreesC, where the mechanism for restricting and the mechanism for heating operate in combination to initiate and sustain a supercritical hydrothermal reaction between the methanol and the water to produce the reaction products comprising off-gases consisting essentially of hydrogen, carbon monoxide, carbon dioxide and methane;    (5) mechanism for cooling the reaction products; and    (6) a glassy polymer interface mechanism for separating the hydrogen from the carbon monoxide, the carbon dioxide and the methane.    DESCRIPTION OF DRAWING(S) - The drawing shows a schematic of supercritical water reformer apparatus.    Heating reactor (30)    Thermocouple (45)    Heat exchanger (50)