Conversion of Levulinic Acid to γ-Valerolactone Using Hydrotalcite-Derived Cu-Ni Bimetallic Catalyst

Abstract

γ-Valerolactone (GVL) is a promising bio-based platform molecule with significant potential for energy applications. The production of GVL via biomass-based levulinic acid (LA) is an important reaction. To enhance the conversion and selectivity of non-precious-metal catalysts in the LA-to-GVL process and to better understand the key factors influencing this conversion, we conducted a series of experiments. In this study, supported Cu-Ni bimetallic catalysts (Cu-Ni2/Al2O3) were prepared using layered double hydroxides (LDHs) as a precursor. Compared with Cu-Ni catalysts synthesized via the conventional impregnation method, the Cu-Ni2/Al2O3 catalysts exhibit higher catalytic activity and stability. The results demonstrated that efficient conversion was achieved with isopropanol as the hydrogen donor solvent, a reaction temperature of 180 °C, and a reaction time of 1 h. The yield of GVL reached nearly 90%, with a decrease of approximately only 6% after six consecutive cycles. The Cu-Ni2/Al2O3 catalyst proved to be effective for converting biomass-derived LA to GVL, offering a route that not only reduces production costs and environmental impact but also enables efficient biomass-to-energy conversion.