CO2 reforming of CH4 over Co–Mg–Al mixed oxides prepared via hydrotalcite like precursors

Abstract Co x Mg 6− x Al 2 (with x  = 0, 2, 4, and 6) mixed oxides catalysts were synthesized via hydrotalcite precursors. The catalytic performance and stability were studied in dry reforming of methane. Regardless of the amount of coke deposited on the Co 6 Al 2 HT500 catalyst, no loss of activity was observed during 24 h on stream indicating that part of this carbon is not poisonous. Co 4 Mg 2 Al 2 HT500 was undergoing a severe deactivation after 11 h on stream. The XRD result revealed an important sintering phenomenon of metal particles. Co 2 Mg 4 Al 2 HT500 has shown a stable performance for 24 h on stream without any deactivation or coke deposition, displaying very good stability. This performance was explained by the stability of crystallite size of metal particles and by the presence of MgAl 2 O 4 phase known for its basic properties.