CO₂ Reforming of Methane over a Highly Dispersed Ni/Mg–Al–O Catalyst Prepared by a Facile and Green Method

Abstract

A novel Ni/Mg–Al–O catalyst has been successfully synthesized by the cation–anion double hydrolysis (CADH) method for carbon dioxide (CO2) reforming of methane. Compared with the Ni/MgO–Al2O3 catalyst prepared by the conventional co-impregnation method, the Ni/Mg–Al–O catalyst exhibited enhanced initial activity and improved long-term stability. Structural characterizations revealed that higher metal dispersion (2.8 times) and better intrinsic activity (1.8 times in terms of turnover frequency at 700 °C) were achieved by ultrasmall Ni nanoparticles (2.1 nm) on the Ni/Mg–Al–O catalyst, leading to the enhanced initial activity. The improved long-term stability of the Ni/Mg–Al–O catalyst was attributed to the superior anti-coke property, which was rationalized by the ultrasmall Ni nanoparticles and abundant basic sites. The present work provides a facile and green method for the synthesis of efficient reforming catalysts and elucidates the mechanisms underlying excellent catalytic performances.