From giant reed to levulinic acid and gamma-valerolactone: A high yield catalytic route to valeric biofuels

The acid hydrothermal conversion of a non-food dedicated feedstock – giant reed (Arundo donax L.) – to levulinic acid (LA) was investigated. LA is a versatile intermediate for the production of biofuels and bio- based chemicals. LA was subsequently hydrogenated to c-valerolactone (GVL), a sustainable liquid and valuable fuel additive and a precursor for the new platform of ‘‘valeric biofuels’’. The straight production of GVL directly from water slurries of giant reed was studied by adopting bifunctional (acid and hydro- genating) catalytic systems based on Ru/C and niobium oxide or niobium phosphate. Mild reaction conditions (only 0.5 MPa of hydrogen and 70 C) are possible for the hydrogenation step. GVL yields up to 16.6 wt.% calculated from the starting weight of dry biomass were reached, with an almost complete and selective conversion of the intermediate LA.