NiCe/γ-Al2O3 coated onto cordierite monoliths applied to Oxidative Dehydrogenation of Ethane (ODE)
•The modified 2 steps method used for the catalytic coating synthesis is adequate.•The catalytic coatings on the cordierite monoliths exhibit excellent adherence.•The Ce/Ni ratio in the obtained catalytic layers is higher than the nominal one.•Ni species interact either with alumina or ceria, both constitute active sites.
The present work investigates the preparation of NiCe/γ-Al2O3 coated cordierite monoliths for oxidative dehydrogenation of ethane (ODE) reaction through a two steps procedure: the primer deposition of a γ-Al2O3 coating consisting in a mixture of micro and nanoparticles via the washcoating method and the latter incorporation of the active phase by impregnation. Moreover, a modification in these two steps was made: the suppression of some calcination steps to save energy in the manufacture process. The structured catalysts, named as Ni(X)Ce(Y)-M, where X = 13 or 19 wt%. Ni and Y = 5 or 8 wt%. Ce respectively, with respect to the alumina loading, were characterized by SEM/EDX, XRD, FTIR, LRS and XPS, and their catalytic activity was tested in the ODE reaction. Furthermore, their mechanical resistance to vibration was studied. Similar results corresponding to the un-promoted system are also presented for comparison. It was found that the co-impregnation of nickel and cerium was affected by the suppression of some calcinations: a preferential absorption of Ce rather than Ni occurred, generating at the end a catalytic coating with a higher Ce/Ni ratio than that of the precursor solution and a lower Ni loading than that of Ni(13)-M. On the other side, in the NiCe-based catalysts the properties of the active sites remained the same despite the increment in the active phase, at a fixed Ce/Ni nominal atomic ratio of 0.17. In the case of the Ni(19)Ce(8)-M system, although the Ni/Al atomic ratios were found lower than those of the nominal ones by EDX and XPS and ethylene selectivity decayed, ethane conversion resulted markedly higher, leading to an improved ethylene yield.
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Journal: Catalysis Today - Volume 273, 15 September 2016, Pages 259–265