Novel Cu/Al2O3-ZrO2 composite for selective hydrogenation of levulinic acid to γ-valerolactone.

Abstract Novel Cu/Al 2 O 3 -ZrO 2 composite catalyst was developed for the catalytic hydrogenation of levulinic acid (LA) to γ- valerolactone (GVL) in water. By increasing Al 2 O 3 content of the Cu/Al 2 O 3 -ZrO 2 composite up to 5.0 wt% resulted in a nearly 3-fold increase in activity, without loss of selectivity towards GVL. This superior catalytic activity can be attributed to the dilution of Cu by Al 2 O 3 as well as the enhanced electronic interaction between Cu and ZrO 2 compared to Cu/ZrO 2 catalyst. Reusability test for four consecutive runs showed a stable activity and selectivity, thus confirming the scope for practical application. Graphical abstract Unlabelled Image Highlights • The 32.3 wt% Cu/5%Al 2 O 3 -ZrO 2 exhibits nearly 3-fold better activity than 34 wt% Cu/ZrO 2. • 100% selectivity to γ-valerolactone remained over the 32.3 wt% Cu/5%Al 2 O 3 - ZrO 2. • The composite showed favor recovery and cyclic utilization properties. [ABSTRACT FROM AUTHOR]