International Journal of Hydrogen Energy, Vol.42, No.17, 12284-12294, 2017
Oxidative steam reforming of ethanol (OSRE) over stable NiCo-MgAl catalysts by microwave or sonication assisted coprecipitation
The present paper reports the physicochemical and catalytic characterization of NiCo-MgAl mixed oxides prepared from hydrotalcite (HT) precursors using ultrasound (US) or microwave radiation (MW)-assisted coprecipitation. The US or MW use reduces the preparation time and enhance both basicity and redox properties of the material compared to the solid obtained by the conventional method (coprecipitation). The oxidative steam reforming of ethanol (OSRE) was performed during 100 h (stability test) with or without solid pre-reduction in order to understand some aspects of the OSRE mechanism when transition metal catalysts are used without activation. The results demonstrate the potential of using 1Ni1Co mixed oxides obtained by MW or US assistance which exhibited better properties and catalytic stability employing shorter synthesis times. Furthermore, experiments conducted without material pre-reduction indicate the sensitivity of OSRE to the basic strength of the surface. A marked increase in basicity decrease H-2 yield because of the formation of C-3 byproducts. (C) 2017 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.
Keywords:Ultrasound;Microwave radiation;Hydrotalcite;Oxidative steam reforming of ethanol;Stability tests