High-performance and stable Ru-Pd nanosphere catalyst supported on two-dimensional boron nitride nanosheets for the hydrogenation of furfural via water-mediated protonation

Bimetallic Ru-Pd catalysts are increasingly being investigated for applications in the upgrading of bio-oils to biofuels, owing to their high catalytic activities. Similarly, the recent development of Ru-Pd alloyed nanoparticle (NP) incorporated into hexagonal boron nitride (h-BN) catalysts that can be utilized for tuning the selectivity of desired products has also received considerable attention. In the present study, nanoclusters of Ru0-Pd0 that self-assemble into spherical-like Ru-Pd bimetallic catalytic sites were successfully grown on the surfaces of BN nanosheets (Ru-Pd/BN NCs) via microwave irradiation for 30 s. HR-TEM investigations revealed the formation of 25 nm sized Ru-Pd nanoparticles comprising ≤ 2 nm hexagonal closed-pack (hcp) Ru-Pd clusters with Ru crystallites on the BN nanosheets. Further, furfural was effectively converted into furfural alcohol at a lower temperature (150 °C) and valuable cyclopentanone was obtained at a higher temperature (>250 °C) over the Ru-Pd/BN catalyst through the protonation of water molecules. Furthermore, various solvents namely 2-propanol, toluene, and cyclohexane were also used to achieve the production of furan and tetrahydrofuran over the Ru-Pd/BN catalyst via the decarbonylation of furfural under mild reaction conditions. Moreover, for real-time upgrading, furfural-rich bio-oil produced by the pyrolysis of date-tree biomass was processed over the Ru-Pd/BN catalyst to obtain a maximum of 97% furfural conversion with a 71% FFA yield at 150 °C. The stability and reusability of the catalyst were also determined. The results demonstrated that the Ru-Pd/BN catalyst is highly active and chemically stable, and is therefore suitable for industrial applications.