(24f) Isosorbide Production from Aqueous Sorbitol Solution over Silica-Aluminas

Isosorbide is an important chemical for the production of fuels, plastics, and pharmaceuticals. Current isosorbide production is from plant biomass. Most current studies have been conducted in non-aqueous systems or pure sorbitol. However, processing plant biomass usually involves water. Thus, isosorbide production in aqueous systems is more practical. In the present study, we investigated the conversion of aqueous sorbitol to isosorbide using amorphous silica-alumina (ASA) with various SiO2/Al2O3 ratios. The isosorbide yield of ~ 56% was achieved at 220ËšC and 22 h. Surface area/pore volume, densities of acid sites, and total acidity of ASA from Brunauer-Emmett-Teller (BET), Fourier transform infrared spectroscopy (FT-IR)-pyridine adsorption and NH3-Temperature Programmed Desorption (TPD), respectively, were found to be responsible for this high isosorbide selectivity in the aqueous system.