Biorefinery of the hazelnut shells (Tonda Gentile Romana). Acid-catalysed hydrothermal treatment for the production of levulinic acid and hydrochar

For the first time, the combined production of levulinic acid (LA) and hydrochar was investigated and optimized starting from hazelnut shells, by using dilute HCl as homogeneous catalyst. For this purpose, the optimization of the reaction was separately carried out both in autoclave and microwave systems and the hydrochars recovered from the each optimized reaction were further characterized by different techniques (FT-IR, elemental and proximate analysis, SEM and BET surface area), in order to compare the two different heating systems and get further information about possible subsequent uses of the hydrochar. For the first time, our approach has allowed the complete exploitation of the hazelnut shells, thus closing the Biorefinery of this waste biomass.