NOVELTY - A flameless distributed combustion (FDC) heated, membrane, steam reforming reactor has a reforming chamber, a flameless distributed combustion chamber, a preheater, and a membrane tube which is in contact with reforming catalyst bed. The membrane tube has an outlet to permeate hydrogen formed in the reforming chamber and pass through the outlet.    USE - The inventive reactor is used in steam reforming for the dehydrogenation of ethylbenzene used in supplying hydrogen in hydrogen fuel cell. It is also used in steam reforming for production of CO2 used in oil recovery in oil wells or methane in coal bed methane formations. (all claimed)    ADVANTAGE - The inventive method has minimal CO as end-product, and has minimum concentration of CO in the hydrogen stream. It is accomplished in one reactor, at lower temperatures than those used in conventional steam methane reforming reactors, constantly removing pure hydrogen, and using as a heat source flameless distributed combustion which provides great improvements in heat exchange efficiency and load-following capabilities to drive the steam reforming section.    DETAILED DESCRIPTION - An FDC heated, membrane, steam reforming (MSR) reactor (1) comprises a reforming chamber containing a reforming catalyst bed. The reforming chamber has an inlet for vaporizable hydrocarbon and steam (5), a flow path for hydrogen and by-product gases resulting from the reforming reactions taking place in the reforming chamber and an outlet for the by-product gases. FDC chamber(s) is in a heat transferring relationship with the reforming catalyst bed to provide a distributed, controlled heat flux by the FDC chamber to the reforming catalyst bed. The combustion chamber comprises an inlet and a flow path for an oxidant, an outlet for combustion gas, a fuel conduit having an inlet for fuel, and fuel nozzles which provide fluid communication from within the fuel conduit to the flow path of the oxidant. The fuel nozzles are sized and spaced along the length of the fuel conduit so that no flame results when the fuel is mixed with the oxidant in the combustion chamber. A preheater is provided for preheating the oxidant to a temperature that when the fuel and the oxidant are mixed in the FDC chamber, the temperature of the resulting mixture of the oxidant and fuel exceeds the autoignition temperature of the mixture. Hydrogen-selective, hydrogen-permeable, membrane tube(s) is in contact with the reforming catalyst bed. The membrane tube has an outlet to permeate hydrogen formed in the reforming chamber into the membrane tube and pass through the outlet. An INDEPENDENT CLAIM is also included for a process for the production of hydrogen, comprising reacting steam with a vaporizable hydrocarbon at 200-700degreesC and at 1-200 bar in a reaction zone containing a reforming catalyst (9) to produce a mixture of primarily hydrogen and carbon dioxide (CO2), with a lesser amount of carbon monoxide (CO). Heat is provided to the reaction zone by employing FDC chamber(s) to drive the reaction. The reaction is conducted in hydrogen-permeable, hydrogen-selective membrane tube(s) to permeate hydrogen formed in the reaction zone through the hydrogen selective membrane tube and separate from the CO2 and CO.    DESCRIPTION OF DRAWING(S) - The figure is a schematic diagram of the inventive membrane steam-reforming reactor.    FDC-MSR reactor (1)    Steam (5)    Membrane (8)    Catalyst (9)