From Lignocellulosic Biomass to Rare Sugars: Hydrolisis and Isomerization with Heterogeneous Catalysts

The PhD project presented in this thesis focused on two research topics turned to contribute to the development of a modern model of production, that is able to reduce the environmental impact of the chemical industry. For this purpose, preparation and characterization of heterogeneous catalysts for the transformation of renewable raw materials into valuable chemicals has been studied. The first part of the work concerned the conversion of lignocellulosic biomass, the most abundant renewable source presents on Earth, into monosaccharides and bio-building blocks, such as HMF, furfural and levulinic acid. Solid acid metal phosphate catalysts were synthetized for lignocellulose transformation; the catalytic behaviors shown by prepared metal phosphates were correlated to their physical-chemical properties: in particular, the role of acid features on the hydrolysis reaction has been studied. The synthesis of interesting industrial monosaccharides that cannot be obtained in appreciable amount from natural resources, called rare sugars, was the topic of the second part of the work. For this purpose, the rearrangement of glucose by the use of heterogeneous catalysts containing titanium was studied: especially, the influence of the different Ti species on products distribution has been investigated.