A comparative study of ZrO2, Y2O3 and Sm2O3 promoted Ni/SBA-15 catalysts for evaluation of CO2/methane reforming performance

Ni-based/SBA-15 catalysts, were promoted by 3wt% of samaria (Sm2O3), Yttria (Y2O3) and Zirconia (ZrO2), by two-solvent impregnation method. The catalysts characterization was performed by N2 adsorption-desorption, X-ray Diffraction (XRD), X-ray Fluorescence (XRF), High Resolution Transmission Electron Microscopy (HRTEM), Field Emission Electron Scanning Microscopy (FESEM), Temperature Programmed Oxidation/Reduction (TPO/TPR) and NH3-Temperature Programmed Desorption (NH3-TPD) techniques. Then, evaluated by CO2/methane reforming. The CO2/methane reforming outcomes revealed that samaria-promoted catalyst showed excellent activity, stability and cock resistance, while yttria-promoted catalyst just illustrated good activity at high temperature and zirconia-promoted catalyst didn't show any modification in catalytic performance in comparison to Ni-based catalyst with no promoter. Samaria-promoted TEM and TPR analysis, indicated adding samaria improved the NiO particles interaction with SBA-15 support pores wall and NiO dispersion. The TPO analysis displayed that coke deposition in samaria-promoted sample after 12 h reaction is less than yttria-promoted during stream of 5 h. Also, it is suggested that for samaria containing catalyst, cock deposition occurred on the support. Therefore, nickel active sites were preserved for time on stream of 12 h, which is the main reason for samaria-promoted catalyst superior stability than other's. (C) 2017 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.