Synthesis and characterization of innovative catalysts for the selective oxidation of 5-hydroxymethylfurfral

The depletion of fossil-derived resources and the need to decrease the emission of green-house gases led scientists to look for sustainable materials to replace the already existing fossil-derived ones. For instance, 2,5-furandicarboxylic acid (FDCA) has been pointed out as the bioderived counterpart of terephthalic acid for the synthesis of polyesters. In fact, FDCA could be obtained by means of selective oxidation of 5-hydroxymethylfurfural (HMF), a bio-derived platform molecule produced by glucose hydrolysis. This reaction is known to be catalyzed by supported metal nanoparticle systems in presence of inorganic bases under batch conditions. This work deals with the development of catalytic systems able to perform the base-free HMF oxidation, since the possibility to circumvent base addition leads more sustainable processes. In particular, two different sets of catalytic systems have been studied: mono- and bimetallic Au and Pd nanoparticles on nano-sized NiO, and mono- and bimetallic Pt/Sn systems on titania, prepared via cluster precursor decomposition. Another topic that will be discussed in this thesis focuses on the development of catalytically active polymeric membranes obtained via electrospinning and their application as catalytic system for HMF oxidation either under basic and neutral aqueous conditions. In details, polyacrylonitrile and nylon have been tested as electrospun polymeric matrixes for the embedding of Au-based nanoparticles and Pt clusers.