Abstract
A Co/MgAl2O4 catalyst with Ce addition was prepared and characterized by different techniques (BET, XRD, SEM-EDX, TPR and TG-TPO). Its catalytic performance was tested in the ethanol steam reforming reaction at 650 °C and a \({\text{W/F}}_{{{\text{C}}_{ 2} {\text{H}}_{ 5} {\text{OH}}}}\) = 50 g min mol−1 using different H2O:C2H5OH molar ratios (MR) in the feed. The presence of Ce on the catalyst markedly increased selectivity of hydrogen (from 3.2 to 5.2 molH2/molC2H5OH for MR = 4.8) and carbon resistance. The increase of the H2O:C2H5OH MR led to a significant decrease in the CO/CO2 ratio (from 0.84 for RM = 4.8 to 0.5 for RM = 8) and in the carbon amount after 7 h on stream (from 22.9 % for RM = 4.8 to 6.8 % for RM = 8). MR higher than 6 did not significantly improve the catalytic performance. Taking into account previous studies about the thermal balance of this reaction, the optimum MR in the ethanol steam reforming seems to be around 6. The ethanol conversion was nearly constant after 7 h in spite of the carbon amount detected by TG-TPO and SEM-EDX. It could be inferred that an important Co fraction was exposed on the filament tips and/or a fraction of carbonaceous species was deposited on the support surface.
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Midilli A, Ay M, Dincer I, Rosen MA (2005) On hydrogen and hydrogen energy strategies: I: current status and needs. Renew Sust Energy Rev 9:255–271
Barreto L, Makihira A, Riahi K (2003) The hydrogen economy in the 21st century: a sustainable development scenario. Int J Hydrog Energy 28:267–284
Balat M, Balat M (2009) Political, economic and environmental impacts of biomass-based hydrogen. Int J Hydrog Energy 34:3589–3603
Ni M, Leung DYC, Leung MKH (2007) A review on reforming bio-ethanol for hydrogen production. Int J Hydrog Energy 32:3238–3247
Liguras DK, Kondarides DI, Verykios XE (2003) Production of hydrogen for fuel cells by steam reforming of ethanol over supported noble metal catalysts. Appl Catal B 43:345–354
Breen JP, Burch R, Coleman HM (2002) Metal-catalysed steam reforming of ethanol in the production of hydrogen for fuel cell applications. Appl Catal B 39:65–74
Busca G, Costantino U, Montanari T, Ramis G, Resini C, Sisani M (2010) Nickel versus cobalt catalysts for hydrogen production by ethanol steam reforming: Ni–Co–Zn–Al catalysts from hydrotalcite-like precursors. Int J Hydrog Energy 35:5356–5366
Batista M, Santos R, Assaf E, Assaf J, Ticianelli E (2003) Characterization of the activity and stability of supported cobalt catalysts for the steam reforming of ethanol. J Power Sources 124:99–103
Llorca J, Homs N, Sales J, de la Piscina P (2002) Efficient production of hydrogen over supported cobalt catalysts from ethanol steam reforming. J Catal 209:306–317
Soykal I, Bayram B, Sohn H, Gawade P, Miller JT, Ozkan U (2012) Ethanol steam reforming over Co/CeO2 catalysts: investigation of the effect of ceria morphology. Appl Catal A 449:47–58
Barroso MN, Gomez M, Arrua L, Abello MC (2010) CoZnAl catalysts for ethanol steam reforming reaction. Chem Eng J 158:225–232
Song H, Ozkan U (2010) Changing the oxygen mobility in Co/Ceria catalysts by Ca incorporation: implications for ethanol steam reforming. J Phys Chem A 114:3796–3801
Ferencz Zs, Erdőhelyi A, Baán K, Oszkó A, Óvári L, Kónya Z, Papp C, Steinrück HP, Kiss J (2014) Effects of support and Rh additive on Co-based catalysts in the ethanol steam reforming reaction. ACS Catal 4:1205–1218
Avila-Neto CN, Zanchet D, Hori CE, Ribeiro RU, Bueno JMC (2013) Interplay between particle size, composition, and structure of MgAl2O4-supported Co–Cu catalysts and their influence on carbon accumulation during steam reforming of ethanol. J Catal 307:222–237
Barroso MN, Gomez MF, Arrua LA, Abello MC (2014) Co catalysts modified by rare earths (La, Ce or Pr) for hydrogen production from ethanol. Int J Hydrog Energy 39:8712–8719
Mattos LV, Jacobs G, Davis BH, Noronha FB (2012) Production of hydrogen from ethanol: review of reaction mechanism and catalyst deactivation. Chem Rev 112:4094–4123
Benito M, Padilla R, Rodriguez L, Sanz JL, Daza L (2007) Zirconia supported catalysts for bioethanol steam reforming: effect of active phase and zirconia structure. J Power Sources 169:167–176
Ioannides T (2001) Thermodynamic analysis of ethanol processors for fuel cell applications. J Power Sources 92:17–25
Francesconi JA, Mussati MC, Mato RO, Aguirre PA (2007) Analysis of the energy efficiency of an integrated ethanol processor for PEM fuel cell systems. J Power Sources 167:151–161
Avila CN, Hori CE, de Assis AJ (2011) Thermodynamic assessment of hydrogen production and cobalt oxidation susceptibility under ethanol reforming. Energy 36:4385–4395
Lin SS-Y, Kim DH, Ha SY (2009) Metallic phases of cobalt-based catalysts in ethanol steam reforming: the effect of cerium oxide. Appl Catal A 355:69–77
Varga E, Ferencz Z, Oszkó A, Erdőhelyi A, Kiss J (2015) Oxidation states of active catalytic centers in ethanol steam reforming reaction on ceria based Rh promoted Co catalysts: an XPS study. J Mol Catal 397:127–133
Mas V, Baronetti G, Amadeo N, Laborde MA (2008) Ethanol steam reforming using Ni(II)-Al(III) layered double hydroxide as catalyst precursor: kinetic study. Chem Eng J 138:602–607
Guo J, Lou H, Zhao H, Chai D, Zheng X (2004) Dry reforming of methane over nickel catalysts supported on magnesium aluminate spinels. Appl Catal A 273:75–82
Nandini A, Pant K, Dhingra S (2005) K-, CeO2-, and Mn-promoted Ni/Al2O3 catalysts for stable CO2 reforming of methane. Appl Catal A 290:166–174
Sánchez-Sánchez M, Navarro RM, Fierro JLG (2007) Ethanol steam reforming over Ni/MxOy–Al2O3 (M = Ce, La, Zr and Mg) catalysts: influence of support on the hydrogen production. Int J Hydrog Energy 32:1462–1471
Ros T, Van Dillen A, Geus J, Koningsberger D (2002) Surface oxidation of carbon nanofibres. Chem Eur J 8:1151–1162
Lin SS-Y, Kim DH, Engelhard MH, Ha SY (2010) Water-induced formation of cobalt oxides over supported cobalt/ceria–zirconia catalysts under ethanol-steam conditions. J Catal 273:229–235
Bayram B, Soykal I, Deak D, Miller J, Ozkan U (2011) Ethanol steam reforming over Co-based catalysts: investigation of cobalt coordination environment under reaction conditions. J Catal 284:77–89
Passos A, Martins L, Pulcinelli S, Santilli C, Briois V (2014) Effect of the balance between Co(II) and Co(0) oxidation states on the catalytic activity of cobalt catalysts for Ethanol Steam Reforming. Catal Today 229:88–94
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Financial supports are acknowledged to CONICET, ANPCyT and Universidad Nacional de San Luis.
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Barroso, M.N., Gomez, M.F., Arrúa, L.A. et al. Effect of the water–ethanol molar ratio in the ethanol steam reforming reaction over a Co/CeO2/MgAl2O4 catalyst. Reac Kinet Mech Cat 115, 535–546 (2015). https://doi.org/10.1007/s11144-015-0852-1
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DOI: https://doi.org/10.1007/s11144-015-0852-1