The conversion of furfural has been investigated in vapor and liquidphases over a series of supported monometallic Pd and bimetallic Pd-Fe catalysts. Over the monometallicPd/SiO 2 catalyst, the decarbonylation reaction dominates, yieldingfuran as the main product. By contrast, over the bimetallic Pd-Fe/SiO 2 catalyst a high yield of 2-methylfuran is obtained with much lower yield to furan. Interestingly, changing the catalyst support affects the product distribution. For instance, using-Al 2 O 3 instead of SiO 2 as support of the bimetallic catalyst changed the dominant product from 2-methylfuran to furan. That is, Pd-Fe/-Al 2 O 3 behaves more like monometallic Pd/SiO 2 than bimetallic Pd-Fe/SiO 2. A detailed characterization of the catalysts via XPS, XRD, and TEM indicatedthat a Pd-Fe alloy is formed on the SiO 2 support but not on the-Al 2 O 3 support.Theoreticaldensity functional theory calculations suggest that on the Pd-Fe alloy binding of the furan ring to the surface is weakened compared to on pure Pd. This weakening disfavorsthe ring hydrogenation and decarbonylation paths, while the oxophilic nature of Fe atoms enhances the interaction of the C=O and theOH groups with the metal surface, whichfavors the C=O hydrogenation and CO bond cleavage paths. The presence of the solvent has a less pronounced effect, but clearly has a stronger inhibition on CC bond cleavage (decarbonylation to furan) than on CO bond cleavage (hydrogenolysis to methyl furan). *FOL = furfuryl alcohol, THF= tetrahydrofuran, MF= 2-methylfuran, THFOL= tetrahydrofurfuryl alcohol, MTHF= 2-methyltetrahydrofuran, CPON =cyclopentanone.

A novel strategy for the synthesis of high-density biofuel using two biomass-derived oxygenated compounds, furfural and guaiacol, with a variety of heterogeneous catalysts is proposed. In the first step of this strategy, furfural is converted with high yields and selectivity to cyclopentanol (CPOL) over Mg-Al supported Cu catalysts. Then, the cyclopentanol is used to alkylate guaiacol over a series of HY zeolites to generate C9–C16 oxygenates with an appropriate molecular weight to be used as transportation fuels. Finally, in the last step of this catalytic strategy, the C-alkylation products are successfully hydrodeoxygenated over ruthenium nanoparticles supported on carbon nanotubes (Ru/MWCNT), producing a liquid mixture of cyclic hydrocarbons with high density (0.865 g mL–1 at 20 °C) and excellent low-temperature properties. This overall reaction route is a promising approach for converting biomass-derived compounds into transportation fuel precursors.

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The aqueous phase hydrodeoxygenation (HDO) of furfuryl alcohol over Cu/MgAl and Cu/ZnAl catalysts with different Mg/Al and Zn/ Al molar ratios, were investigated. Mg-Al and Zn-Al mixed oxides derived from hydrotalcites precursors were used as supports, which were impregnated with an aqueous solution of copper nitrate by incipient wetness impregnation. The HDO reaction was carried out in a typical batch reactor at 5 MPa of H 2 and 200 °C for 4 h. Among the catalysts studied, the Cu/MgAl-0.5 catalyst exhibited the higher furfuryl alcohol conversion (86 %) and yield of cyclopentanol (35 %), which is the reaction product with the highest hydrogencarbon (H/C) ratio. With the Cu/MgAl-3 catalyst a high cyclopentanone yield (67 %) was achieved. The results obtained, showed that copper supported on mixed oxides catalysts derived from hydrotalcite precursors are a promising alternative to improve the bio-oil quality.Keywords: Hydrotalcites, cyclopentanol, furfuryl alcohol, copper, bio-oil upgrading. RESUMENSe investigó la hidrodesoxigenación(HDO) del furfuril alcohol sobre catalizadores de Cu/MgAl y Cu/ZnAl con diferentes relaciones molares Mg/Al y Zn/Al. Óxidos mixtos de Mg-Al y Zn-Al derivados de precursores tipo hidrotalcitas se usaron como soporte, los cuales fueron impregnados con una solución acuosa de nitrato de cobre, mediante el método de impregnación húmeda. La reacción de hidrodesoxigenación (HDO) se realizó en un reactor tipo batch a 5 MPa de H 2 y 200 °C por 4 h. Entre los catalizadores estudiados, el catalizador de Cu/MgAl-0.5 exhibió la más alta conversión del furfuril alcohol (86 %) y rendimiento hacia ciclopentanol (35 %), el cual es el producto de reacción con mayor relación hidrógeno-carbono (H/C). Con el catalizador de Cu/MgAl-3 se logró un alto rendimiento hacia ciclopentanona (67 %). Los resultados obtenidos, mostraron que los catalizadores de óxidos mixtos derivados de precursores tipo hidrotalcitas son una alternativa prometedora para mejorar las características del bio-oil.Palabras clave: Hidrotalcitas, ciclopentanol, furfuril alcohol, cobre, mejora del bio-aceite.