Abstract
ZrO2 supported Nickel catalyst, 9 wt%WO3-91 wt%ZrO2 supported Nickel catalyst and ceria promoted 9 wt%WO3-91 wt%ZrO2 supported Nickel catalyst (5NixCe/WZr catalyst) is synthesized via wet impregnation and characterized by XRD, UV-vis, CO2-TPD, H-2 TPR-CO2 TPD-H-2 TPR cycle, TPH, TPH followed by O-2-TPO and CO2-TPD followed by O-2-TPO. Due to limitation in surface re-oxidizing capability and shading of catalytic active sites by thermally stable carbonates; catalytic activity of unpromoted catalyst system is less. 5NixCe/WZr catalyst has extended CH4 decomposition sites, additional basic sites (during the reaction) for CO2 adsorption and excellent redox accompany (Ce (+4)/Ce (+3), W+(6)/W (+4)) for carbon oxidation and re-oxidizing capability of surface up to the pristine level. 2.5 wt% Ceria promotional addition is resulted into 78% H-2 yield constantly up to 420 min TOS. The carbon deposit over ceria promoted system (up to 2.5 wt%) is amorphous type, more easily/moderately reducible, oxidizable and removable. (C) 2021 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.