Ni particles generated in situ from spinel structures used in ethanol steam reforming reaction

Abstract

The in situ generation of Ni particles from a spinel structure used in the ethanol steam reforming reaction was studied. A series of Ni1-xCuxAl2O4 (x=0, 0.01, 0.05, 0.1) catalysts precursors were synthesized by the citrate method. Samples were characterized by SBET, X-ray diffraction, neutron powder diffraction, temperature-programmed reduction, X-ray photoelectron spectroscopy, thermogravimetric-mass spectrometry, scanning electron microscopy, and hydrogen chemisorption. The inclusion of Cu into the spinel structure was beneficial to facilitate the exsolution of Ni particles to the surface at lower reduction temperatures, and thus it was essential to generate highly dispersed particles on the spinel surface. Ni0.9Cu0.1Al2O4 catalyst presented the highest H2 selectivity and low mean values of CO selectivity, around 15% with zero formation of methane.