UC Berkeley

Sn-BEA zeolite is known to catalyze the aldose-to-ketose isomerization of xylose and glucose; however, the selectivity to pentose and hexose isomers is not stoichiometric, suggesting the formation of other products. In the present study, we have observed near-complete conversion of all pentose and hexose isomers when xylose and glucose were reacted in the presence of Sn-BEA at 140 °C and 200 °C, respectively. The previously unidentified products were identified by nuclear magnetic resonance and mass spectrometry to be hydroxyalkanoic acids and their derivatives. The hydroxyl-rich acids comprise a significant fraction of the converted sugars and are potential monomers for the synthesis of hyper-crosslinked, biodegradable polymers.