Hydrogen production from ethanol steam reforming over core-shell structured NiOxOy-, FexOy-, and CoxOy-Pd catalysts

The present work focused on the investigation of the hydrogen generation through the ethanol steam reforming over the core-shell structured NixOy-, FexOy-, and CoxOy-Pd loaded Zeolite Y catalysts. The transmission electron microscopy (TEM) image of NixOy-Pd represented a very clear core-shell structure, but the other two catalysts, CoxOy- and FexOy-Pd, were irregular and non-uniform. The catalytic performances differed according to the added core metal and the support. The core-shell structured CoxOy-Pd/Zeolite Y provided a significantly higher reforming reactivity compared to the other catalysts. The H-2 production was maximized to 98% over CoxOy-Pd(50.0 wt%)/Zeolite Y at the conditions of reaction temperature 600 degrees C, CH3CH2OH:H2O = 1:3, and GHSV (gas hourly space velocity) 8400 h(-1). In the mechanism that was suggested in this work, the cobalt component played an important role in the partial oxidation and the CO activation for acetaldehyde and CO2 respectively, and eventually, cobalt increased the hydrogen yield and suppressed the CO generation. (C) 2010 Professor T. Nejat Veziroglu. Published by Elsevier Ltd. All rights reserved.