LaFe0.9Ni0.1O3 perovskite catalyst with enhanced activity and coke-resistance for dry reforming of ethane

Abstract

A LaFe0.9Ni0.1O3 perovskite catalyst was evaluated for dry reforming of ethane (DRE), with two conventional oxide supported Ni catalysts (Ni/La2O3 and NiFe/La2O3) being used as references. LaFe0.9Ni0.1O3 showed the best activity and high coke-/sintering-resistance. TEM, TGA, and Raman characterizations confirmed that the deactivation of Ni/La2O3 was owing to the growth of Ni particles and the accumulation of coke, although the formation of La2O2CO3 was able to remove part of the coke during the reaction. The introduction of Fe-related species inhibited the coke formation while decreased the activity due to the loss of active sites. A portion of Ni ions in the perovskite lattice could be reduced to form highly dispersed and stable Ni nanoparticles on the surface during the reaction and oxygen vacancies were left in the perovskite lattice. Pulse reactor studies revealed that the oxygen vacancies in the perovskite could facilitate the activation and dissociation of CO2 to form CO and reactive oxygen species. Moreover, C2H6 was activated with the assistance of oxygen from the surface or subsurface of LaFe0.9Ni0.1O3 to form CO, rather than directly dissociated to surface carbon species as observed over Ni/La2O3.