Ru supported on micro and mesoporous carbons as catalysts for biomass-derived molecules hydrogenation

Supported ruthenium based materials are active for the catalytic hydrogenation of biomass-derived molecules. However, such catalysts still have problems regarding deactivation coming from Ru leaching and particles aggregation. In this work we demonstrate that spatial restriction on metal nanoparticles limits aggregation and eliminates performance losses upon subsequent testing. We synthesized and compared Ru supported on activated (Ru/AC) or mesoporous carbon (Ru/MC). Electron tomography characterization showed preferential Ru location depending on the material porosity; Ru nanoparticles were located inside mesoporous carbon pores and showed narrower size distribution. In catalytic reactions, Ru/MC reached the complete conversion of levulinic acid with the 96% selectivity to γ-valerolactone while it converted 74% of glycerol compared to the 34% showed by Ru/AC. The Ru/AC materials deactivated after 1 catalytic cycle, however the Ru/MC maintained constant activity for multiple catalytic cycles.