Ternary Ni-Al-Fe catalysts for ethanol steam reforming

Ternary mixed oxides prepared from takovite/reevesite Ni3Al1-xFex precursors were tested in ethanol steam reforming for hydrogen production. The influence of the trivalent cation (Al3+ or Fe3+) on phase composition and derived catalytic performance of the resulting oxides was studied. The physico-chemical properties of the hydrotalcite-like precursors and related oxides were characterized by ICP, XRD, TGA-DSC, Raman, H-2-TPR, and TEM analyses. Compared to pure binary systems (Ni3Al and Ni3Fe), the ternary systems showed the best performance in ethanol reforming, leading to high and stable hydrogen selectivity of up to ca. 70% in 100 h reaction tests. The increase in activity can be attributed to a cooperative effect between aluminum and iron, favoring ethanol dehydrogenation as the primary step, followed by acetaldehyde reforming and/or cracking, reverse water gas shift, and methanation, and concomitantly limiting the dehydration route to ethylene.