In a context of rarefaction and increasing of prices of fossil energetic resources, it is necessary to diversify the energetic offer. Hydrogen seems to be one of the most promising vectors, although technological matters associated to its production slow down its development. In this context, the present work aims at elaborating a system able to produce pure hydrogen from hydrocarbon, and in particularly from methane. It is constituted of three membranes, which specific roles are reforming, separation and restitution of molecular hydrogen. The first membrane is porous and is made of a cermet BaCe0.85Y0.15O3-a / nickel. The second one is dense and is elaborated either simply from BaCe0.85Y0.15O3-a, or from the same cermet as the first membrane, depending whether the system operates in a galvanic or in a non-galvanic mode. The last one is of the same nature and morphology as the first one. The three membranes are fabricated and coupled one with the others by the process called co-tape-casting in organic solvent followed by a step of co-sintering. More precisely, on the free surface of the first membrane a layer of a mixture of powders Xj / Ni, where Xj and Ni are respectively the support and the catalyst for methane cracking reaction (Xj = CeO2, Silica, Nanodiamonds, zeolithes,...), is deposited via a humid route. Then, by feeding with methane this system, with for example the presence of the highly efficient couple CeO2/Ni, the production of hydrogen is made possible and deposited carbon atoms form nanotubes with Ni particles at their tops, which are then always in the methane flux, and which then do not suffer from deactivation. Hydrogen enters then in the porosity of the first membrane where it is oxidized when meeting with triple phases boundaries. In a non-galvanic system, protons and electrons can go through the second membrane, following the percolating proton and ion conducting paths, to reach the third membrane. In a galvanic system, electrons are transported toward the third membrane via an external circuit, which imposes a voltage. At the third membrane triple phase boundaries, electrons and protons recombine to form pure molecular hydrogen. These two systems galvanic and non galvanic have been designed and fabricated, and the motivation that has led to the choice of the materials used was given at each step of the process. Thanks to the comprehension of the different phenomena taking place during operating conditions, a rather optimized process leading to a system of production and purification of hydrogen was realized. Finally, a numeric model was developed, in order to tailor the influence of all the different parameters that may influence the performances of the object.
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