Hydrogen production through oxidative steam reforming of ethanol over Ni-based catalysts derived from La1−xCexNiO3 perovskite-type oxides
This paper investigates the effect of lanthanum substitution by cerium oxide on the performance of La1−xCexNiO3 (x = 0, 0.05, 0.1, 0.4, 0.7 and 1.0) perovskite-type oxide precursor for the oxidative steam reforming of ethanol. All catalysts are active and selective to hydrogen but carbon deposition occurs except for La0.90Ce0.10NiO3. Increasing the Ce content decreases the amount of carbon deposited, which passes through a minimum at around 10 wt% of Ce and then increases. The higher resistance to carbon formation on La0.90Ce0.10NiO3 catalyst is due to the smaller Ni crystallite size. Furthermore, the support also plays an important role on catalyst stability during ethanol conversion reaction. The reduced La0.9Ce0.1NiO3 sample exhibits the highest amount of oxygen vacancies, which decreases as ceria content increases. This highly mobile oxygen reacts with carbon species as soon as it forms, and thus keeps the metal surface free of carbon, inhibiting deactivation.
Graphical abstractFigure optionsDownload full-size imageDownload as PowerPoint slideHighlights► The incorporation of Ce into the LaNiO3 structure affected the catalyst stability. ► La0.90Ce0.10NiO3 catalyst exhibited better stability in OSR of ethanol. ► No carbon formation was observed on La0.90Ce0.10NiO3 catalyst. ► La0.90Ce0.10NiO3 has smaller Ni particle size and higher amount of oxygen vacancies.
Journal: Applied Catalysis B: Environmental - Volumes 121–122, 13 June 2012, Pages 1–9