Biogas Reforming for Hydrogen Production: A New Path to High-Performance Nickel Catalysts Supported on Magnesium Aluminate Spinel

摘要

Highly dispersed Ni nanoparticles supported on high-surfacearea mesoporous nanocrystalline MgAl2O4 powder was generated by a facile and simple propylene oxide assisted gelation agent route. The mesoporous spinel materials exhibited enhanced catalytic performance for hydrogen production in biogas dry reforming. The obtained spinel catalysts with different Ni loadings after calcination at 700 degrees C possessed high BET surface areas (236-224 m(2)g(-1)). A narrow pore size distribution in the mesopore range was observed in the samples, and all the samples except 2.5 wt% Ni showed a mesoporous-macro-porous structure. The 5 wt% Ni/MgAl2O4 sample showed the highest activity for the biogas dry reforming reaction because of the high dispersion of Ni on the mesoporous surface of the spinel support. X-ray photoelectron spectroscopy revealed that the catalysts with a low Ni loading undergo the exchange of Mg2+ by Ni2+, whereas catalysts with a higher Ni loading undergo the substitution of Al3+ by Ni3+. Thus, appropriate partial Ni substitution in the MgAl2O4 support may play a role in the elevated catalytic performance.