Highly Efficient Transfer Hydrogenation of Levulinate Esters to γ-Valerolactone over Basic Zirconium Carbonate

Novel and selective strategies for platform chemical production from renewable biomass are highly attractive in respect to value-added utilization of sustainable resources. In this study, a series of low-cost, commercially available, transition metal carbonates (Zr, Ni, Mg, Zn, and Pb) were investigated for catalytic transfer hydrogenation of levulinate esters to γ-valerolactone (GVL) via the cascade process of Meerwein–Ponndorf–-Verley (MPV) reduction and lactonization reaction. Among the selected catalysts, basic zirconium carbonate is the most active, with the highest turnover frequency (TOF) of 3.1 h–1 and a surface reaction rate of 0.21 mol m–2 h–1. At 453 K, 3.0 h, and 1.0 MPa N2, 100% ethyl levulinate conversion, 96.3% GVL yield, and 91.9% hydrogen donor utilization are observed due to the cooperative effect between acid (Mn+) and base (−OH) sites. Furthermore, this catalyst shows high recyclability under the optimized conditions, where a satisfactory catalytic activity is shown even after six consecutive runs.