Highly efficient CuNi–ZrO2 nanocomposites for selective hydrogenation of levulinic acid to γ-valerolactone

Abstract

CuNi–ZrO₂ nanocomposites were prepared by a simple coprecipitation technique of copper, nickel and zirconium ions with potassium carbonate. The structures of the nanocomposites were characterized by N₂ physical adsorption, XRD, H₂-TPR and STEM-EDS. The Cu_0.05Ni_0.45–ZrO₂ nanocomposite showed outstanding catalytic performance in hydrogenation of levulinic acid (LA) to γ-valerolactone (GVL), especially NaOH solution (0.5 mol L⁻¹) as a solvent. 100% LA conversion and > 99.9% GVL selectivity are achieved over Cu_0.05Ni_0.45–ZrO₂ catalyst at 200 °C, 3 MPa for 1.5 h. Characterization results suggest that the excellent reactivity of the Cu_0.05Ni_0.45–ZrO₂ may be due to a better reducibility of nickel oxide in the CuONiO–ZrO₂, dispersion of Ni in the Cu_0.05Ni_0.45–ZrO₂ compared to nickel oxide in the NiO–ZrO₂ and Ni in the Ni_0.5–ZrO₂ and promotion of OH⁻. The results demonstrate that the Cu_0.05Ni_0.45–ZrO₂ nanocomposite has potential to realize high efficiency and low-cost synthesis of liquid fuels from biomass.