Catalytic ethanol steam reforming

Aupretre, F., Descorme, C., and Duprez, D. Hydrogen production for fuel cells the catalytic ethanol steam reforming. Topics in Catalysis, 2004, 30-31 (1), 487. 

Therdthianwong, A., Sakulkoakiet, T., and Therdthianwong, S. Hydrogen production by catalytic ethanol steam reforming. Science Asia, 2001 27, 193. 

Ethanol can be derived from biomass by means of acidic/enzymatic hydrolysis or also by thermochemical conversion and subsequent enzymatic ethanol formation. Likewise for methanol, hydrogen can be produced from ethanol with the ease of storage/transportation and an additional advantage of its nontoxicity. Apart from thermodynamic studies on hydrogen from ethanol steam reforming,117-119 catalytic reaction studies were also performed on this reaction using Ni-Cu-Cr catalysts,120 Ni-Cu-K alumina-supported catalysts,121 Cu-Zn alumina-supported catalysts,122,123 Ca-Zn alumina-supported catalysts,122 and Ni-Cu silica-supported catalysts.123... 

Small reformers R D areas include compact and low cost reformers (1-5 kW) to convert fossil fuels (natural gas, gasoline) or biomass fuels (ethanol) to hydrogen via different processes (steam reforming, partial oxidation, auto-thermal, non catalytic hybrid steam reforming). Improvements in reformer efficiency, capacities and response times, and integration of purification unit are also being studied. Examples of projects include ... 

We tested BaRhxZr(i.x)03 (5 wt.% Rh) for ethanol steam reforming [13] finding that an almost complete ethanol conversion (99.7%) was achieved at reasonably low temperature (550°C) with a hydrogen selectivity of roughly 68 mol%. Best catalytic performances were exhibited by the sample calcined at higher temperature (900°C), and this was again attributed to the more pure perovskitic structure, with better Rh interspersion. 

These systems were tested in several catalytic reactions, giving promising results for methane rich combustion and ethanol steam reforming (BaRhxZr(i. x)03), and for methane lean combustion (BaPdxZr(i x)03). 

Llorca et developed a micro-channel reactor where ethanol steam reforming is performed on one side of the plate while ethanol combustion is performed on the with 14 microchannels. The results revealed that Rh-based catalysts exhibited the highest catalytic activity, when compared to Co and Ni. The Rh-Ni-Ce catalyst was operated for 100 h without any noticeable degradation in activity and selectivity. Full conversion was achieved for the entire period and the Hg selectivity was 86%. The CO content in reformate remained constant ca. 8.2%. 

Lopez, E., Divins, N.J. and Llorca, J. (2012) Hydrogen production from ethanol over Pd-Rh/Ce02 with a metallic membrane reactor. Catalysis Today, 193, 145-150. Montane, D., Bolshak, E. and Abello, S. (2011) Thermodynamic analysis of fuel processors based on catalytic-wall reactors and membrane systems for ethanol steam reforming. Chemical Engineering Journal, 175, 519-533. 

Yu, C.Y., Lee, D.W., Park, S.J. et al. (2009) Study on a catalytic membrane reactor for hydrogen production from ethanol steam reforming. International Journal of Hydrogen Energy, 34, 2947-2954. 

Kaddouri, A., Mazzocchia, C. (2004). A study of the influence of the synthesis conditions upon the catalytic properties of Co/Si02 or C0/AI2O3 catalysts used for ethanol steam reforming. Catalysis Communications, 5, 339—345. 

Homs et al. reported that nickel supported on zinc oxide is not a favourable catalyst formulation for ethanol steam reforming, but the addition of nickel to a cobalt/zinc oxide catalyst promoted with sodium increased the catalytic activity [206]. At S/C 6.5 and only 300 °C reaction temperature, full ethanol conversion could be achieved without by-product formation, apart from methane. 

J., and Gandia, L.M. (2011) Computational fluid dynamics simulation of ethanol steam reforming in catalytic wall microchannels. Chem. Eng. /., 167 (2-3), 603-609. 

Resini, C., Montanari, T., Barattini, L., et al. (2009). Hydrogen production by ethanol steam reforming over Ni catalysts derived from hydrotalcite-like precursors. Catalyst characterization, catalytic activity and reaction path, Appl.Catal. A Gen., 355, pp. 83-93. 

Figure 8.8 Schematic representation of the catalytic hollow fiber MMR for hydrogen production using ethanol steam reforming reaction.

Concerning heterogeneous catalytic systems, Rh is an active metal for the ethanol steam reforming to produce H2. In the reforming the sup-... 

C. Liang, Z. Ma, H. Lin, L. Ding, J. Qiu, W. Frandsen, and D. Su, 2009, Template preparation of nanoscale CexFei.x02 sohd solutions and their catalytic properties for ethanol steam reforming, J. Mater. Chem., 19,1417-1424... 

Steam Reforming of Ethanol Even though all the samples containing 20 wt.% or above of Ni exhibited similar activity and selectivity (Table 11.6), their stability over a 500 h duration run varied sample 6A, with 40% Ni and a Ce02/Zr02 ratio of 1 was the most stable. The Ce/Zr ratio has a marked effect on the catalytic stability of these materials. 

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