Copper-based catalysts synthesized during hydrogenation

Impregnation is a traditional method for preparing heterogeneous catalysts, which typically includes impregnation, calcination and reduction steps. In this study, catalyst preparation was combined with its use in catalytic hydrogenation for avoiding ex-situ catalyst-synthesis. Specifically, Cu/MgO were prepared by simply mixing CuSO 4 , MgO and the reactant to be hydrogenated such as levulinic acid (LA) or ethyl levulinate (EL) in ethanol with hydrogen. Heating of the mixture to 160 °C could obtain both synthesized Cu/MgO and hydrogenation product of gamma-valerolactone (GVL) (highest yield: 99.9%). The formation of Cu/MgO catalyst proceeded via the steps of fixing Cu 2+ by reacting with the basic sites of MgO to form Cu(OH) 2 . The metastable Cu(OH) 2 decomposed to form CuO that was reduced to Cu for catalyzing conversion of LA/EL to GVL. Such a method is very simple and applicable to prepare varied types of Cu-based catalyst by changing copper salts and supports of varied alkalinity.