Carbons from second generation biomass as sustainable supports forcatalytic systems

In this study activated carbons were produced from the wood of three different wood species (pine, birch, spruce). The resulting activated carbons were characterized in bulk for ash content, carbon content (elemental analyses), specific surface area, and pore size distribution, and at the surface by measuring the autogenerated pH and studying their structure by XPS. All the samples presented high surface areas and appeared to be mesoporous materials (mesopores >80%). The carbons were then used as support for AuPt nanoparticles and tested in the liquid phase oxidation of glycerol (GLY) and in the hydrogenation of levulinic acid (LA), two important chemicals from cellulose-based biomass. The catalytic results showed that the catalyst activity depends on the structural features of carbons: in GLY oxidation the most active catalyst presents the lowest content of carboxylic acid (Birch derived carbon) whereas in LA hydrogenation an higher content of aliphatic structure seems to enhance the stability and therefore the activity of the catalyst (Spruce catalyst). The structure of the carbons does not affect greatly the selectivity of both selected model reactions.