International Journal of Hydrogen Energy, Vol.42, No.16, 11333-11345, 2017
Dry reforming of methane to syngas over lanthanum-modified mesoporous nickel aluminate/gamma-alumina nanocomposites by one-pot synthesis
La-modified NiAl2O4/gamma-Al2O3-La composites with mesoporous structures were prepared by one-pot template-free strategy and applied for dry reforming of methane (DRM) to syngas. The characterization results confirmed that these materials possessed high specific surface areas, large pore volumes and narrow pore size distributions. The reduced catalysts exhibited excellent catalytic properties as well as long-term stability for DRM reaction. Addition of La showed little influence on the catalyst structure and the mean sizes of metal Ni particles, but could enhance the medium-strength basicity and the accumulation of Ni2+ on the catalyst surface, resulting in the enhancement of intrinsic activity, the reduction of apparent activation energy, and the suppression of carbon deposition for DRM reaction. The catalyst containing 3 wt% La possessed the best catalytic performance. The characterization of spent catalysts also demonstrated that La could effectively prevent the phase transformation of gamma-alumina in the DRM process. (C) 2017 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.
Keywords:Nickel catalyst;Mesoporous gamma-alumina;La-modifier;Nickel aluminate;Methane dry reforming