In this study, a zirconium tungstate-zirconia (ZrW2O8-ZrO2) bifunctional solid acid catalyst was synthesized via a one-pot hydrothermal approach and investigated for the production of n-butyl levulinate (n-BL) from biomass-derived substrates. Comprehensive catalytic characterization using XRD, BET, FT-IR, TEM, XPS, NH3-TPD and Pyridine-IR confirmed the coexistence of cubic ZrW2O8 and monoclinic ZrO2 phases within a mesoporous framework, providing a balanced distribution of accessible Br & oslash;nsted and Lewis acidic sites. The catalytic performance of ZrW2O8-ZrO2 was tested for the esterification of levulinic acid (LA) and furfuryl alcohol (FOL) with n-butanol under milder reaction conditions. Systematic variation of reaction parameters identified optimal operating conditions, under which LA esterification achieved 94% conversion with 83% n-BL selectivity, while FOL esterification reached 90% conversion with 95% n-BL selectivity, demonstrating the versatility of the catalyst towards different biomass-derived feedstocks. The catalyst also exhibited good structural and catalytic stability, maintaining conversion and selectivity over five consecutive reuse cycles. Overall, the study demonstrates that coupling bifunctional acidity with mesoporous mixed-oxide architecture enables efficient and stable production of n-butyl levulinate from biomass-derived precursors, highlighting ZrW2O8-ZrO2 (1:1) as a robust heterogeneous catalyst for sustainable ester synthesis.

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