A series of FeOx-MeOy/Mg(Al)O catalysts were prepared from hydrotalcite-like compounds as precursors and were tested in the ethylbenzene dehydrogenation to styrene in He atmosphere at 550 degrees C The hydrotalcite-like precursors of the metal compositions of Mg3Fe0 25Me0 25Al0 5 (Me = Cu Zn Cr Mn Fe Co and Ni) were coprecipitated from the nitrates of metal components and calcined to mixed oxides at 550 C After the calcination the mixed oxides showed high surface area of 150-200 m(2) g(cat)(-1) and were mainly composed of (MgMe)(Fe3+ Al)O penclase in the bulk whereas the surface was enriched by (MgMe)(Fe3+ Al)(2)O-4 pinel Among the Me species tested Co2+ was the most effective followed by Ni2+ Co2+ addition increased the activity of original FeOx/Mg(Al)O catalyst whereas Ni2+ increased the activity at the beginning of reaction but deactivated the catalyst during the reaction The other metals formed isolated MeOx species in the catalyst resulting in a decrease in the activity compared to the original FeOx/Mg(Al)O catalyst The active Fe species exists as metastable Fe3+ on the FeOx/Mg(Al)O catalyst By the addition of Co2+ the reduction-oxidation between Fe3+ and Fe2+ was facilitated and moreover the active Fe3+ species was stabilized It is likely that the dehydrogenation proceed on the active Fe3+ species via its reduction-oxidation assisted by Co2+ (C) 2010 Elsevier B V All rights reserved