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Hydrogenolysis of cork has been examined using a range of precious metal catalysts studying the effect of the support, added base and solvent used. The addition of a catalyst and a base resulted in a bio-oil increase of 9.3–158% compared to when no catalyst was used along with an increase in the lipid yield of 113–258%. The change in the solvent to 2-methyl tetrahydrofuran from the original dioxane solvent system allowed for a change to a “greener” solvent as well as an increased bio-oil yield from 11.5 wt% to 42.6 wt%, in the absence of a base. [ABSTRACT FROM AUTHOR]

Ketones, derived via the selective ring-opening hydrogenation of biomass-derived furanic compounds, are useful synthons for the production of fuels and lubricant. In this study, 2,5-dimethylfuran (DMF) was used as a model to investigate the liquid-phase hydrogenation of substituted furans over noble metals. The activity and selectivity of carbon-supported Pt, Pd, Rh, and Ru were compared under identical conditions. Pt/C exhibited the highest activity and selectivity for C O bond hydrogenolysis, whereas all other catalysts exhibited a high selectivity for ring hydrogenation to form 2,5-dimethyltetrahydrofuran. The reaction kinetics were measured in detail for liquid-phase hydrogenation of DMF over Pt/C, under conditions that excluded the effects of internal or external mass transfer (333 K–363 K, p H2 = 0.41–0.69 MPa). A reaction mechanism is proposed to explain the parallel formation of 2,5-dimethyltetrahydrofuran, 2-hexanone, and 2-hexanol. This mechanism is consistent with what is known about the adsorption of DMF on Pt, and explains why ring opening occurs directly from adsorbed DMF and not via secondary reaction of 2,5-dimethyltetrahydrofuran. The kinetics of DMF hydrogenation are well represented by the mechanism and the assumption of non-competitive adsorption of organic species and hydrogen atoms. The step involving C O bond cleavage of the aromatic ring had the highest activation energy, 45.4 kJ/mol, and is favored over the steps involving C C bond hydrogenation of the furan ring at elevated temperatures and low p H2 . The reaction kinetics reveal that DMF hydrogenation can be tuned to produce 2-hexanone with 92% selectivity at 100% conversion under relatively mild liquid phase conditions (0.41 MPa, 393 K). [ABSTRACT FROM AUTHOR]