Preparation of cobalt-copper-aluminum spinel mixed oxides from layered double hydroxides for total oxidation of benzene

Mixed metal oxides Co5 - xCuxAl (x = 0-05) were prepared from Co-Cu-Al layered double hydroxides (LDHs) and tested for benzene total oxidation. By calcination, Co-Cu-Al LDHs were mainly transformed to (Co, Cu)(Co, Al)(2)O-4 spinels, where both Cu2+ and Al3+ cations were incorporated into the spinel structure. The incorporation of Cu significantly improved the Co oxide reducibility and remarkably enhanced the light-off activity as well as the total conversion activity, indicative a strong interaction between Cu2+ and Co3+ active sites. The optimum Co4.75Cu0.25Al spinel mixed oxide was comparable with a 03%Pd/gamma-Al2O3 catalyst, highlighting the promoting effect of structural modification with Cu. (C) 2016 Elsevier B.V. All rights reserved.