Ni nanoparticles prepared from Ce substituted LaNiO sub(3) for the guaiacol conversion

The effect of the substitution of cerium on the catalytic conversion of guaiacol over Ni-based catalysts prepared from the reduction of La sub(1- x)Ce sub(x)NiO sub(3) perovskite-type oxides (0.0 [< or =] x [< or =] 0.9) has been investigated. The thermal behavior under reductive atmosphere indicates a beneficial effect of Ce addition. The characterization of the calcined La sub(1-x)Ce sub(x)NiO sub(3) perovskites and reduced Ni-based catalysts by atomic absorption spectroscopy (AAS), adsorption of N sub(2) (-196[degrees]C), transmission electron microscopy (TEM), X-ray powder diffraction and temperature programmed reduction (TPR) revealed significant differences in crystalline structure and reducibility. The Ni-reduced materials were effective in catalyzing the conversion of guaiacol to cyclohexanol. The catalysts with Ce content x [< or =] 0.3 displayed similar initial intrinsic rate. The highest activity was obtained for the catalysts with Ce content x = 0.5 and 0.7 which was ascribed to the highest thermal stability under reductive atmosphere of CeO sub(2)-solid solution partially substituted with La. The Ni-reduced catalysts displayed a high selectivity to cyclohexanol and methoxycyclohexanol compounds and the catalysts with X sub(Ce) = 0.5 presented a high stability in the guaiacol conversion.