Bio-ethanol steam reforming: Insights on the mechanism for hydrogen production

Abstract New catalysts for hydrogen production by steam reforming of bio-ethanol have been developed. Catalytic tests have been performed at laboratory scale, with the reaction conditions demanded in a real processor: i.e. ethanol and water feed, without a diluent gas. Catalyst ICP0503 has shown high activity and good resistance to carbon deposition. Reaction results show total conversion, high selectivity to hydrogen (70%), CO2, CO and CH4 being the only by-products obtained. The reaction yields 4.25 mol of hydrogen by mol of ethanol fed, close to the thermodynamic equilibrium prediction. The temperature influence on the catalytic activity for this catalyst has been studied. Conversion reaches 100% at temperature higher than 600 °C. In the light of reaction results obtained, a reaction mechanism for ethanol steam reforming is proposed. Long-term reaction experiments have been performed in order to study the stability of the catalytic activity. The excellent stability of the catalyst ICP0503 indicates that the reformed stream could be fed directly to a high temperature fuel cell (MCFC, SOFC) without a further purification treatment. These facts suggest that ICP0503 is a good candidate to be implemented in a bio-ethanol processor for hydrogen production to feed a fuel cell.

[1]  A. Kiennemann,et al.  Hydrogen production by ethanol reforming over Rh/CeO2–ZrO2 catalysts , 2002 .

[2]  Edson A. Ticianelli,et al.  Characterization of the activity and stability of supported cobalt catalysts for the steam reforming of ethanol , 2003 .

[3]  Xenophon E. Verykios,et al.  Production of hydrogen for fuel cells by steam reforming of ethanol over supported noble metal catalysts , 2003 .

[4]  C. Marshall,et al.  Catalytic decomposition of alcohols, including ethanol, for in situ H2 generation in a fuel stream using a layered double hydroxide-derived catalyst , 2003 .

[5]  J. Llorca,et al.  Direct production of hydrogen from ethanolic aqueous solutions over oxide catalysts , 2001 .

[6]  Feng Wu,et al.  Hydrogen from steam reforming of ethanol in low and middle temperature range for fuel cell application , 2004 .

[7]  A. Kaddouri,et al.  A study of the influence of the synthesis conditions upon the catalytic properties of Co/SiO2 or Co/Al2O3 catalysts used for ethanol steam reforming , 2004 .

[8]  Ilie Fishtik,et al.  A thermodynamic analysis of hydrogen production by steam reforming of ethanol via response reactions , 2000 .

[9]  O. Yamamoto,et al.  Difference in the reactivity of acetaldehyde intermediates in the dehydrogenation of ethanol over supported Pd catalysts , 1999 .

[10]  Theophilos Ioannides,et al.  Thermodynamic analysis of ethanol processors for fuel cell applications , 2001 .

[11]  P. Tsiakaras,et al.  Hydrogen production by ethanol steam reforming over a commercial Pd/γ-Al2O3 catalyst , 2004 .

[12]  J. Rasko,et al.  Surface species and gas phase products in steam reforming of ethanol on TiO2 and Rh/TiO2 , 2004 .

[13]  M. Jobbágy,et al.  Cu-Ni-K/γ-Al2O3 supported catalysts for ethanol steam reforming: Formation of hydrotalcite-type compounds as a result of metal–support interaction , 2003 .

[14]  P. Irving,et al.  Steam Reforming of Hydrocarbon Fuels , 2002 .

[15]  G. Maggio,et al.  Ethanol steam reforming in a molten carbonate fuel cell: a thermodynamic approach , 1996 .

[16]  H. Idriss,et al.  The Reactions of Ethanol over Au/CeO2 , 2004 .

[17]  Pilar Ramírez de la Piscina,et al.  Efficient Production of Hydrogen over Supported Cobalt Catalysts from Ethanol Steam Reforming , 2002 .

[18]  Xenophon E. Verykios,et al.  Reaction network of steam reforming of ethanol over Ni-based catalysts , 2004 .

[19]  M. Laborde,et al.  Bio-ethanol steam reforming on Ni/Al2O3 catalyst , 2004 .

[20]  G. Bonura,et al.  Steam reforming of bio-ethanol on alkali-doped Ni/MgO catalysts: hydrogen production for MC fuel cell , 2004 .