NOVELTY - Producing hydrogen from a hydrocarbon fuel, involves combining the fuel with a gas containing oxygen and/or steam; and passing the fuel and gas mixture through a plasma (40) generated by a microwave plasma generator (13) between opposed electrodes (20, 22) in a microwave plasma reactor (10), in which at least one of the electrodes defines a duct (24) for outflow of material from the vicinity of the plasma so that the gas mixture emerging from the outflow duct contains hydrogen. The fuel and the gas enter the reactor so as to form a swirl of fuel and gas mixture around the electrodes.    USE - For producing hydrogen from a hydrocarbon fuel, such as diesel fuel (claimed), kerosene and petrol (gasoline).    ADVANTAGE - The process achieves complete fuel conversion by a single pass of the fuel and gas mixture through the microwave plasma reactor. The swirling fuel and gas mixture causes the fuel and gas mixture to form a vortex at the centre of the cell between the two electrodes leading to good mixing of the fuel with the gas comprising oxygen and/or steam. The process effectively generates hydrogen from hydrocarbon fuel; achieves high fuel conversions despite the short residence times and provides high throughput yield. The removal of the gas mixture through one of the electrodes increases the likelihood that the gases pass through the plasma as the entrance to the outflow duct is located in the plasma.    DETAILED DESCRIPTION - An INDEPENDENT CLAIM is included for a system comprising a microwave plasma reactor and a fuel cell, where the microwave plasma reactor comprises a reaction chamber coupled to a microwave plasma generator, at least one pair of opposed electrodes in the reaction chamber and perpendicular to the direction of propagation of microwave radiation through the reaction chamber, at least one inlet for fuel and a gas comprising oxygen and/or steam in the chamber positioned so as to cause gas passing through the electrodes to form a swirl around the electrodes and at least one of the electrodes defining a duct for outflow of material from the vicinity of the plasma.    DESCRIPTION OF DRAWING(S) - The figure shows a diagrammatic flow diagram of a hydrogen generating apparatus incorporating a microwave plasma reactor.    microwave plasma reactor (10)    microwave plasma generator (13)    reaction chamber (16)    electrodes (20, 22)    outflow duct (24)    outlet duct (26)    hydrogen generating apparatus (32)    plasma. (40)