Yttrium modified Ni-based double-layered hydroxides were tested as novel catalysts in dry methane reforming. The catalysts were characterized by XRF, BET analysis, XRD, TPR-H 2 , TPD-CO 2 , TGA/DSC-MS, H 2 chemisorption and TEM. Co-precipitation with yttrium (III) nitrate hexahydrate resulted in increased specific surface area, smaller Ni crystallite size, enhanced reducibility, and higher distribution of weak and medium basic sites as compared to Y-free material. The DRM catalytic tests, carried out in the temperature range of 850-600 ºC, led to a significant improvement of activity, with the 1.5 wt % Y-promoted catalyst being the most efficient in converting both CH 4 and CO 2. Moreover, the 10 h test at 700 ºC further confirmed enhanced stability for this HTNi-Y1.5 catalyst. Higher CO 2 conversion than CH 4 conversion and less CO compared to H 2 proves that side reactions are occurring simultaneously.

Dry reforming of methane was studied over Ni,Y-promoted KIT-6 ordered mesoporous silicas, prepared by incipient impregnation (nickel content 12 wt.%, yttrium content of 4 wt.%, 8 wt.% or 12 wt.%). The catalysts were characterized by XRF, FT-IR, TGA/DSC-MS, N2-adsorption, TEM, HRTEM, XRD and TPR-H2. The promotion with 8 wt.% Y (Y/Si=0.05) resulted in the highest activity and H2/CO molar ratio closer to the stoichiometric value at temperatures from 600 to 750°C. The characterization results of the yttrium promoted materials showed higher reducibility of the bulk NiO, bigger Ni crystallite size after reduction and DRM test, and better dispersion of nickel in the channels of the KIT-6 support. Additionally, larger Ni particles were observed on the external surface of the support, which may be related to catalytic selectivity towards carbon forming reactions. Upon dry methane reforming the segregated phases of Niº, Y2O3, and possibly Y2Si2O7 were registered. No presence of a Ni,Y alloy was observed.