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Herein we present a high yield 2-methylfuran production process with the required features to be implemented in a future integrated biorefinery. The strategy is based on the right solvent selection, 2-methyltetrahydrofuran, which i) can be used to extract the reactant, furfural, from the aqueous solution obtained after corncob biomass hydrolysis; ii) allows for highly selective 2-methylfuran production form furfural with up to 80% yields and iii) presents suitable biofuel properties in the gasoline range. Using this innovative approach, two energy intensive separation steps are avoided: the initial furfural purification and the final solvent/product complete separation. Further benefits of this process arise from the developed low-cost, selective, and reusable Cu-Co/γ-Al2O3 catalyst.

Three aluminium oxide materials and a HZSM-5 zeolite were used as supports of bimetallic Pt-WOx catalysts, in order to establish structure-activity relationships in the glycerol hydrogenolysis reaction. The tungsten surface density and the intimate contact between Pt and WOx showed to be key parameters. Tungsten surface density controls the formation of polytungstates, the only species able to produce the weak Bronsted acidity that is required to selectively produce 1,3-propanediol. The comparison between the HZSM-5 and the Al2O3 supports demonstrated that an increment on the medium Bronsted acidity is detrimental for the selective 1,3-propanediol formation, as it promotes the reactions that yield 1-propanol and propane. Increasing the dispersion of Pt for the Pt/WOx/Al2O3 catalysts led to larger glycerol conversion values, but promoted the hydrogenolysis routes that lead to 1,2 and 1,3-propanediol similarly. On the contrary, increasing the Pt metal content significantly favoured the hydrogenolysis route leading to 1,3-propanediol. A more intimate contact between Pt and WOx promoted the hydrogenation of the intermediate carbocation, formed and stabilized on a polytungstate active site, into 1,3- propanediol.

SSCI-VIDE+ATARI+SGF:SBE:AAU; International audience; Although the hydrogenolysis of glycerol to 1,2-propanediol is already well developed, the production of the more valuable 1,3-propanediol is still a challenge. To achieve this aim, it is essential to design catalysts showing high selectivity toward the CO cleavage of the secondary hydroxyl group in glycerol. In this work, two different series of Pt/WOx/Al2O3 catalytic systems were studied for the selective hydrogenolysis of glycerol to 1,3-propanediol. The results reveal the necessity to control the tungsten surface density in order to obtain highly dispersed polytungstate species, which are able to produce Bronsted acidity and are involved in the selective formation of 1,3-propanediol. After optimization of the tungsten surface density, the effect of platinum content was also studied. It was found that by improving the interactions between platinum and tungsten oxides, it is possible to increase the selectivity toward 1,3-propanediol. Under optimized conditions, a selectivity toward 1,3-PDO of 51.9% at 53.1% glycerol conversion was obtained. Based on the characterization and activity test results, a reaction mechanism for the Pt-WOx catalytic system in glycerol hydrogenolysis to 1,3-propanediol was also proposed. (C) 2015 Elsevier Inc. All rights reserved.