International Journal of Hydrogen Energy, Vol.42, No.27, 16979-16990, 2017
Influence of MgO content as an additive on the performance of Ni/MgO-SiO2 catalysts for the steam reforming of glycerol
Ni catalysts supported on MgO-SiO2 were assessed in the steam reforming reaction of glycerol for the study of the H-2 production and carbon deposition with different MgO contents as additives. The catalysts were prepared with commercial SiO2 by the aqueous impregnation method and characterized by energy dispersive X-ray spectroscopy, specific surface area, X-ray diffraction, thermogravimetric analysis, X-ray diffraction in situ with O-2, temperature programmed reduction with H-2, X-ray diffraction in situ with H-2, temperature programmed desorption with H-2 and scanning electron microscopy. The glycerol steam reforming reaction took place at 600 degrees C for 5 h, with a water/glycerol molar ratio of 12/1 at 5 mLh(-1). N-2 was used as the carrier gas. The characterization of the samples showed the interaction of Ni with the support increases with the MgO addition, due to the formation of a Ni Mg silicate hydrate and MgNiO2 solid solution; as a result, both metallic area and dispersion also increased. Catalytic results showed similar gaseous products yields (H-2, CH4, CO and CO2) for mixed-matrix catalysts, however, a lower carbon deposition on 10 wt%Ni catalyst supported on 30 wt%MgO SiO2 was observed. (C) 2017 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.