Hydrogen production by catalytic decomposition of selected hydrocarbons and H2O dissociation over CeZrO2 and Ni/CeZrO2

Presented paper deals with the catalytic decomposition of hydrocarbons (methane and toluene) in the aspect of H2 production and types of obtained carbon deposits. The catalyst used in our studies was nickel supported on ceria–zirconia (Ni/CeZrO2). The aim of this work was to investigate the reactivity of obtained carbon deposits with H2O. Both issues are of great importance for determining the mechanisms of carbon deposits formation and their suppression during steam reforming reaction. udies revealed that depending on the temperature, CH4 decomposition over Ni/CeZrO2 leads to carbon nanotubes (CNTs), whereas C7H8 decomposition yields pyrolytic carbon. Hydrogen production was found to be higher for CH4 decomposition. Both types of carbon deposits (filamentous and pyrolytic) were found to be very reactive with H2O, which is due to their activation by the ceria–zirconia support. tic tests of hydrocarbon decomposition and H2O dissociation were carried out in the temperature-programmed mode and isotherms, and were supported by the in situ reflectance FT-IR measurements. Obtained carbon deposits were characterized using high-resolution transmission electron microscopy (HRTEM).