(119f) Intensifying Interaction of Glycerol Acetalization and Mass Transfer By Modified HY Zeolites

This study explores the surface hydrophobicity as a strategy to intensify mass transfer between reactants’ interface for glycerol acetalization to solketal. Bronsted acids catalyze this reaction. Zeolites have been used in this reaction. Although this reaction is stoichiometric, very diluted glycerol has been used because of the low solubility of glycerol in acetone (~5 wt.%). This low solubility leads to a low equilibrium conversion. One of the current solutions is to operate at a high reaction temperature to improve the glycerol solubility. Although an increase in reaction temperature can improve the equilibrium conversion, it comes with an increase in capital expenditure (CAPEX) and operating expenditure (OPEX) of the process. We hypothesize that hydrophobicizing zeolites with organosilanes allow them to disperse at the interface between glycerol and acetone, enhancing the mass transfer between glycerol and acetone and resulting in higher glycerol conversion. Here we show that adding hydrophobic layers to HY zeolites enhances dispersion of catalysts at the interface. We obtained 94% glycerol conversion at 30°C and high acetone to glycerol molar ratio of 17. This strategy can be applied to other solid acid catalysts in other acid-catalyzed reactions where feed solubility is an issue.