The catalytic transfer hydrogenation of furfural to the fuel additives 2-methylfuran (2-MF) and 2-methyltetrahydrofuran (2-MTHF) was investigated over various bimetallic catalysts in the presence of the hydrogen donor 2-propanol. Of all the as-prepared catalysts, bimetallic Cu-Pd catalysts showed the highest catalytic activities towards the formation of 2-MF and 2-MTHF with a total yield of up to 83.9 % yield at 220 °C in 4 h. By modifying the Pd ratios in the Cu-Pd catalyst, 2-MF or 2-MTHF could be obtained selectively as the prevailing product. The other reaction conditions also had a great influence on the product distribution. Mechanistic studies by reaction monitoring and intermediate conversion revealed that the reaction proceeded mainly through the hydrogenation of furfural to furfuryl alcohol, which was followed by deoxygenation to 2-MF in parallel to deoxygenation/ring hydrogenation to 2-MTHF. Finally, the catalyst showed a high reactivity and stability in five catalyst recycling runs, which represents a significant step forward toward the catalytic transfer hydrogenation of furfural.

An efficient and robust bimetallic catalyst has been developed for the transfer hydrogenation of biomass derived ethyl levulinate to γ-valerolactone with 2-butanol as the hydrogen donor. Several bimetallic catalysts were prepared and characterized by Brunauer−Emmett−Teller, transmission electron microscopy, X-ray power diffraction and X-ray photoelectron spectrometry. They exhibited different catalytic activities in the catalytic transfer hydrogenation (CTH) reaction. Results showed that 10Cu-5Ni/Al 2 O 3 had the highest activity, providing a 97% yield of GVL product in 12 h at 150 °C. The reaction temperature, reaction time and catalyst loading were also investigated and found to affect the product yield. The catalyst was also successfully applied to the CTH of various levulinate esters with different secondary alcohols. Comparing experiments between Cu−Ni and Cu catalysts and the poisoning experiments revealed that the introduction of Ni to Cu remarkably enhanced the catalyst's activity and stability, showing an outstanding recycling ability in the 10 runs recycling experiments without notable loss in the activity.

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The esterification of the biomass derived platform molecule, levulinic acid, to its alkyl levulinates was carried out over metal salt catalysts under microwave condition, which achieved near-quantitative product yields in a few minutes.

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