Ru-CeO2 and Ni-CeO2 Coated on Open-Cell Metallic Foams by Electrodeposition for the CO2 Methanation

CO2 methanation structured catalysts, made by a layer of Ru-CeO2 or Ni-CeO2 (Ru/Ce = 3/97; Ni/Ce = 1/3 and 3/1) on open-cell NiCrAl foams, are prepared by electrodeposition and a subsequent calcination step. The performance of the catalysts at a space velocity of 320,000 mL g(cat)(-1) h(-1) in a feedstock with H-2/CO2/N-2 = 4/1/1 v/v, significantly depends on the Ni content and the preparation method. A low Ru or Ni content promotes the metal-CeO2 interaction, the formation of defects in CeO2 as well as the development of a lower amount of cracks in the coating; however, the catalysts show a poor CO2 conversion and selectivity to CH4. The CH4 production rate at low temperature largely increases for the high Ni loaded catalyst, 68.7 L-C(H4) g(Ni)(-1) h(-1) at 350 degrees C oven temperature. This productivity is similar to the value obtained with a Ni3Cel pellet catalyst prepared by the coprecipitation method, a behavior not achievable for low Ru- and Ni-loaded catalysts.