Studio dell'ossidazione selettiva della 5-idrossimetilfurfurale con catalizzatori Pt-Sn ottenuti da cluster carbonilici

This work has been focused on the synthesis and characterization of new mono- and bimetallic Pt and PtSn catalysts using as precursor clusters and inorganic salts. PtSn catalysts were prepared by employing the bi-metallic carbonyl cluster salts [PPh4]4[Pt6(CO)6(SnCl2)2(SnCl3)4] (molar ratio Pt/Sn=1) and [PPh4]2[Pt6(CO)8(SnCl2)(SnCl3)2(PPh3)2] (molar ratio Pt/Sn=2), and for comparison, platinum sample was prepared by employing the homometallic [PPh4]2[Pt12(CO)24]. The prepared catalysts were tested in the selective aqueous phase oxidation of 5-hydroxymethylfurfural to 2,5-furandicarboxylic acid in base-free condition. The characterization by BET, XRD, TEM, H2-TPR was performed over all the catalysts tested, in order to investigate their properties, with particular attention to the interaction between Pt and Sn and its influence on the catalytic activity. The catalytic activity was found to be strongly dependent on PtSn ratio and on the different species which can be formed using different thermal treatment conditions.