This work reports the design, manufacturing and experimental results of a novel silicon-based micro-reactor for hydrogen generation from various fuels: alcohols or hydrocarbons. The micro-reactor is fabricated with well-established microfabrication technologies ensuring a cost-effective, high reproducibility and reliability. The design of the micro-reactor is based on an array of more than 4x104 vertical micro-channels perfectly aligned crossing a 500-μm silicon substrate and through which the fuel flows. The projected area of the micro-reactor is 15x15 mm~2, while the reactive area (considering the micro-channels walls) is more than 36 cm~2. This means a huge active surface per projected area of ～16 cm~2/cm~2. The micro-channels are coated with the catalytic system by infiltration. The high surface-to-volume ratio of the micro-channels array, i.e. 8x10~4 m~2/m~3, leads to high performances of fuel reforming reaction by achieving large specific contact area and short diffusion length. The proposed silicon-based micro-reactor design also includes an integrated micro-heater for heating the system up to the operation temperature autonomously. Ethanol and methane are currently considered as some of the most feasible candidates for hydrogen generation, in order to fuel a micro-SOFC system [1]. Hydrogen formation from ethanol is based on steam reforming, whereas from methane hydrogen can be obtained by dry reforming or partial oxidation. In this work, a catalytic system based on Rh-Pd nanoparticles supported on CeO2 is presented. The micro-reformer has been tested with both ethanol and methane at the optimal temperature for a micro-SOFC system operation. Results demonstrate that the micro-reformer can operate with both fuels, providing acceptable hydrogen production rates to supply a micro-SOFC system. This novel functional converter is the basis for a complete gas processing unit as a subsystem of an entire micro-SOFC system.
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