Characterization of Ni-Mg-Al mixed oxides and their catalytic activity in oxidative dehydrogenation of n-butane and propene

Hydrotalcite-type materials with different Ni:Mg:Al ratios have been prepar ed and characterized by different methods (powder X-ray diffraction, differ ential thermal analysis and thermogravimetric analysis, FT-IR and VIS-UV/di ffuse reflectance spectroscopies and specific surface area and pore size di stribution assessment). Samples calcined at 600 degreesC, where the layered structure has been destroyed, are formed by non-stoichiometric NiO-MgO oxi des, and their catalytic activity in n-butane and propene oxidative dehydro genation has been studied; production of methane and ethylene, in addition to CO2 and H2O, is observed. The sample without Ni is not active in these r eactions, but, among those containing Ni, that with the lowest content exhi bits the largest activity. (C) 2001 Elsevier Science B.V. All rights reserv ed.