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This work is devoted to the investigation of the effect of alkali and alkaline earth metals addition on Ni/ ZrO 2 catalyst activity in high-temperature cellulose conversion. The catalysts containing 20 % of Ni and 1 % of Ca, Mg, Na and K (calculated per amount of oxide) introduced on ZrO 2 surface by impregnation method were prepared. The surface properties of the investigated samples were characterized by X-ray diffraction, temperatureprogrammed reduction, flame atomic absorption spectrometry, scanning electron microscopy and energy-dispersive X-ray spectroscopy. The composition of the gaseous products was identified using gas chromatography. The performed studies demonstrated that introduction of alkali and alkaline earth metals on the surface of nickel catalyst resulted in the considerable increase in the production of hydrogen in comparison with Ni/ZrO 2 reference sample. The highest hydrogen yield was formed in the presence of the catalyst modified by calcium.

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The aim of this work was to determine changes in the surface composition and structure of different biomass samples submitted to high temperature treatment. Cellulose and lignocellulosic biomass were pyrolysed in a stirred batch reactor under atmospheric pressure at 700 °C for 4 h. The reaction was executed without and in the presence of Ni/ZrO2 catalyst. Different biomass samples and the remaining residues after the pyrolysis were investigated by time‐of‐flight SIMS, infrared spectroscopy, and SEM. The results of the studies showed an alteration of the surface of materials submitted to high temperature treatment in comparison to untreated specimens. The composition of uppermost layer of biomass samples influenced the reaction yield and was notably different after pyrolysis in the presence of the catalyst. Copyright © 2014 John Wiley & Sons, Ltd.