LaFeO 3-supported nano Co-Cu catalysts for higher alcohol synthesis from syngas

Abstract

To produce Co-Cu catalysts supported on perovskite-type oxides of LaFeO 3, we prepared LaFe 0.7Cu 0.3O 3 according to the citrate complexation method; the impregnation method was used to load cobalt oxide onto the support. The Co 3O 4/LaFe 0.7Cu 0.3O 3 catalysts were characterized by XRD, TEM, TPR, XPS and S BET analysis, and were used to catalyze the synthesis of alcohol from syngas. Copper ions in the perovskite lattice were easily segregated by pre-reduction, which resulted in the formation of nano-sized copper metal. The copper nano-particles catalyzed the reduction of Co 3O 4, which led to the production of highly dispersed copper nano-particles covered by a metallic cobalt shell of core–shell structure Cu@Co and Cu-Co alloy supported on perovskite-type oxides of LaFeO 3. During the reaction, Cu-Co and La 2O 3 facilitated the formation of Co 2C, and the phase of the catalyst precursor changed to Co 2C-Cu/La 2O 2CO 3-LaFeO 3. The prepared catalysts were highly active, selective and stable during the synthesis of alcohol from syngas. The high activity and selectivity of the catalysts were attributed to the presence of copper-modified Co 2C species, which were highly dispersed nano-particles located on the LaFeO 3 surface. The good stability of the catalysts was attributed to the interactions between Co 2C-Cu nano-particles and their support.