Catalysis Today, Vol.250, 166-172, 2015
Effect of the bimetallic Ni/Cu loading on the ZrO2 support for H-2 production in the autothermal steam reforming of methanol
Bimetallic Ni/Cu/ZrO2 catalysts were prepared by successive impregnation and, the effect of the bimetallic Ni/Cu content on the ZrO2 support was evaluated in the autothermal steam reforming of methanol (ASRM) for H-2 production. The catalytic activity was increased with the bimetallic Ni/Cu content on the ZrO2. Ni/Cu/ZrO2 catalyst with 15% of bimetallic phase loading exhibited the highest selectivity towards H-2. Characterization by TEM-EDX of this catalyst evidenced Cu-core-Ni-shell nanoparticles with quasi-spherical shape. Whilst the shell of the nanoparticles in the 30Ni/Cu/ZrO2 sample was constituted by Ni-Cu alloy, in this catalyst a lower H-2 production was observed. The correlation between size, shape and frequency of these particles on the ZrO2 could be responsible of the catalytic activity and selectivity on each catalyst during the ASRM. We suggest that the large Ni-Cu crystallites with Ni-Cu alloy shell are responsible for the drop of H-2 selectivity in the autothermal steam reforming of methanol. (C) 2014 Elsevier B.V. All rights reserved.