Bio-Based ethyl levulinate production from Biomass-Derived xylose and empty palm fruit bunch using Zirconium-Beta catalysis

ZrO₂ incorporated onto Beta zeolite demonstrated high reactivity and selectivity in converting biomass-derived xylose to ethyl levulinate (EL) without the need for external hydrogen. The active sites in ZrO₂, in conjunction with the confinement control provided by the BEA structure, enhance the rate of dehydration, transfer hydrogenation, and ethanolysis, effectively converting xylose via furfural (FF) and furfuryl alcohol (FA) to EL. The highest yields of EL were achieved at 40.3, 21.5 and 52.9% from xylose, xylan and empty fruit bunch (EFB), respectively. Characterization of ZrO₂ dispersed on Beta zeolite indicates its critical role in the catalytic transfer hydrogenation step. Proper tuning of Brønsted and Lewis acid sites efficiently drives the conversion of biomass-derived xylose to EL. Additionally, the Zr-Beta catalysts can be reused up to three times with minimal decline in EL production and the catalyst can be regenerated to achieve more than 90% of its initial activity in both xylose and EFB reactions.