CONICET | Buscador de Institutos y Recursos Humanos

The solid oxide fuel cells (SOFC) enable the efficient generation of clean energy, fitting the current requirementsof the growing demand for electricity and for the environment preservation. When powered with biogas(from digesters of municipal wastes), the SOFCs also contribute to reduce the environmental impact of thesewastes. The most suitable route to produce hydrogen inside SOFC from biogas is through dry reforming butthe catalyst is easily deactivated by coke, because of the high amounts of carbon in the stream. A promisingway to overcome this drawback is by adding a second metal to nickel-based catalysts. Aiming to obtain active,selective and stable catalysts for biogas dry reforming, solids based on nickel (15%) and copper (5%) supportedon aluminum and magnesium oxide were studied in this work. Samples were prepared by impregnating thesupport with nickel and copper nitrate, followed by calcination at 500, 600 and 800 ºC. It was noted that allsolids were made of nickel oxide, nickel aluminate and magnesium aluminate but no copper compound wasfound. The specific surface areas did not changed with calcination temperature but the nickel oxide averageparticles size increased. The solids reducibility decreased with increasing temperature. All catalysts were activein methane dry reforming, leading to similar conversions but different selectivities to hydrogen and differentactivities in water gas shift reaction (WGSR). This behavior was assigned to different interactions betweennickel and copper, at different calcination temperatures. All catalysts were active in WGSR, decreasing thehydrogen to carbon monoxide molar ratio and producing water. The catalyst calcined at 500 oC was the mostpromising one, leading to the highest hydrogen yield, besides the advantage of being produced at the lowestcalcination temperature, requiring less energy in its preparation.

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