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The green utilization of biomass waste and its eco-friendly conversion into biofuels and value-added chemicals play a crucial role in resolving energy demand and environmental pollution. Herein, we report a win–win strategy to utilize biomass waste to fabricate functional materials and then transform biomass-derived source into valuable products. We developed a one-step strategy using the green solvent CO2 deposition method to spatially confine monometallic Pd and Pt and bimetallic Pd–Pt nanoparticles in a porous carbon fabricated from biomass waste sorghum at a very low temperature of 40–70 °C. The synthesized monometallic Pd and Pt and bimetallic Pd–Pt nanoparticles display superior performance in the selective conversion of biomass-based furfural into fine chemicals, furfuryl alcohol and tetrahydrofurfuryl alcohol. With only 3 wt % Pd or 3 wt % Pt supported on the synthesized porous carbon, these catalysts are far superior to the commercial 5 wt % Pd or Pt on carbon support, respectively. The turnover number of the as-prepared 3 wt % Pd/C catalyst shows ∼7 times improvement compared with the commercial 5 wt % Pd/C. This study provided a one-step method to precisely confine monometallic Pd and Pt and bimetallic Pd–Pt in the porous channel of the carbon support, offered more catalytic active sites, and presented excellent performance and high stability. The methodology developed in this work is promising for the synthesis of various metallic nanoparticles and valorization of biomass.

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In this work, one-pot synthesis of biofuel g-valerolactone (GVL) and valeric acid (VA) from biomass-derived levulinic acid (LA) are highly selectively produced on a series of robust Pdnanoparticle catalysts. These fine Pd nanoparticles are controllably synthesized and confined in the mesoporous channel of MCM-41-derived supports via a green solvent CO 2 -assited method. A combination analysis tools are used to study physical properties and elucidate the relationship between the structure and performances. The catalytic results display 5 wt% Pd/AlMCM-41 exhibits the best performances of 88.5% GVL yield at the perfect conversion of LA. Moreover, without the isolation of GVL intermediate, it can also efficiently catalyze the one-pot conversion of LA to VA with 45.1% yield. Besides, Pdnanoparticle catalysts maintain stable structure and good catalytic performances over several runs.

We demonstrated that the direct change of solvent could tune the highly selective synthesis of biofuels γ-valerolactone (GVL) or levulinate esters from the hydrogenation levulinic acid (LA) over magnetic Ni/C catalysts fabricated from a nickel− metal organic framework (Ni-MOF) precursor. Yields were 98.2% and 86.1% of GVL with almost perfect selectivity when 1,4-dioxane and isopropanol were used as the solvent, respectively. Levulinate esters (86.5% yield of methyl levulinate and 45.6% yield of ethyl levulinate) were synthesized in methanol and ethanol solvents under identical conditions. This work offers an attractive strategy for the selective production of biofuels in the process of biomass feedstocks.