Upgrading of aromatic compounds in bio-oil over ultrathin graphene encapsulated Ru nanoparticles

Fast pyrolysis of biomass for bio-oil production is a direct route to renewable liquid fuels, but raw bio-oil must be upgraded in order to remove easily polymerized compounds (such as phenols and furfurals). Herein, a synthesis strategy for graphene encapsulated Ru nanoparticles (NPs) on carbon sheets (denoted as Ru@G-CS) and their excellent performance for the upgrading of raw bio-oil were reported. Ru@G-CS composites were prepared via the direct pyrolysis of mixed glucose, melamine and RuCl 3 at varied temperatures (500800 C). Characterization indicated that very fine Ru NPs (2.5 1.0 nm) that were encapsulated within 12 layered N-doped graphene were fabricated on N-doped carbon sheets (CS) in Ru@G-CS-700 (pyrolysis at 700 C). And the Ru@G-CS-700 composite was highly active and stable for hydrogenation of unstable components in bio-oil (31 samples including phenols, furfurals and aromatics) even in aqueous media under mild conditions. This work provides a new protocol to the utilization of biomass, especially for the upgrading of bio-oil. A novel Ru@G-CS composite, in which 12 layered N-doped graphene encapsulated nano-sized Ru (2.5 1.0 nm) particles, was fabricated on carbon sheets (CS) via the direct pyrolysis of mixed glucose, melamine and RuCl 3 . And Ru@G-CS-700 (pyrolysis at 700 C) is highly active, selective and stable for the hydrogenation of model compounds (such as phenols, furfurals and aromatics) in bio-oil in water.