Ru on N-doped carbon supports for the direct hydrogenation of cellobiose into sorbitol

With the aim to produce the platform molecule sorbitol from biomass, the two-steps transformation of the cellobiose disaccharide by hydrogenation/hydrolysis was attempted using a single catalytic material. The two reactions were first studied separately before integration. Ru nanoparticles deposited on carbon supports were tested for the hydrogenation of glucose into sorbitol. The optimal nanoparticles size was established. Two different types of carbon materials (activated coal and graphene nanoplatelets) were modified to incorporate nitrogen atoms within the carbon lattice. These N-doped carbon materials displayed higher basicity but showed no activity for the hydrolysis of cellobiose into glucose. They were used to support Ru nanoparticles and these bifunctional catalysts were studied for the hydrogenolysis of cellobiose into sorbitol. Kinetic studies showed that the doping of the carbon supports increased the activity of the Ru nanoparticles for this reaction, going through a hydrogenation followed by disaccharide splitting pathway rather than vice versa. Catalysts were reused and no sign of deactivation have been observed