Commodity Chemicals from Biomass: Catalytic Conversion of Biomass into α,ω-Diols

In this presentation we describe a multi-step catalytic approach for conversion of cellulose into 1,6-hexanediol and hemicellulose into 1,5 pentanediol. These α,ω-diols are high-volume (130,000 tons/year), high value ($4,600/ton) commodity chemicals used in the polymer industry. Cellulose is first converted levoglucosan which is then dehydrated into levoglucosenone (LGO) in the condensed phase with dilute acid (5-20 mM acid concentration) using a polar, aprotic solvent. The product selectivity is a function of the water concentration, the solvent type and the cellulose loading. Increasing the water content leads to the production of 5-hydroxymethylfurfural. The LGO is then hydrogenated into dihydrolevoglucosenone, levoglucosanol, and tetrahydropyran-2-methanol (THPM). The THPM then undergoes selective C-O-C hydrogenolysis to produce 1,6-hexanediol using a bifunctional (reducible metal with an oxophilic promoter) catalyst with > 90% selectivity to 1,6 hexanediol. The hemicellulose is converted into furfural which then undergoes a series of three reactions to produce 1,5 pentanediol.