Catalytic Upgrading of Oxigenated Building Blocks in Lignocellulose- based Biorefineries

This PhD project is focused on the gas phase hydrogenation of furfural over iron and magnesium oxides. Numerous catalysts with different iron and magnesium molar ratios, were prepared by co-precipitation or impregnation methods and were tested for the reduction of furfural (FU) using methanol as hydrogen donor. Furfuryl alcohol (FAL) and 2-methyl furfural (MFU) were the main products obtained, demonstrating that Mg/Fe/O systems can promote sequential hydrogenation-hydrogenolysis reaction. Impregnated catalysts demonstrated to be more active and selective towards MFU than co-precipitated ones. Reported data demonstrated that product distribution was strongly influenced by the iron content and from the resulting acid and redox properties of the material. As a matter of fact, the introduction of iron on the surface of the basic oxide led to the addition of Lewis acidity and redox capacity in the system, significantly enhancing FU conversion and MFU production. The activation of different species on the catalyst surface has been studied by in situ DRIFTS and FTIR. The results reveal that the MgO basicity favors methanol activation and FeOx redox capacity might be the responsible of furfuryl alcohol hydrogenolysis.