Glycerol Transformation to Value-Added 1,3-Propanediol Production: A Paradigm for a Sustainable Biorefinery Process

The impact of diminishing fossil fuel resources, rising environmental issues as well as the global demand for energy, fuels and chemicals has significantly directed to the use of renewable biomass for sustainable production of fuels and chemicals. Glycerol, a three carbon feedstock, is one of the most promising biomass resources which at present is obtained as a by-product in large quantities during the biodiesel production. This stimulated a lot of interest in developing new valorization tech-nologies to produce high-value tonnage chemicals from glycerol by sustainable processes such as oxidation, dehydration, hydrogenolysis, steam reforming, car-boxylation, acetalization, esterification and chlorination. In this chapter, we intend to focus on the hydrogenolysis of glycerol which produces important commodity chemicals such as propanediols, propanols and ethylene glycol. In particular, the selective hydrogenolysis of glycerol to 1,3-propanediol performed in both liquid phase and vapor phase reaction processes is described. Furthermore, the most significant progress in the development of the catalytic materials for glycerol hydrogenolysis including the reaction pathways is herein summarized.