Facile Conversion of Levulinic Acid and Glucose to γ-Valerolactone over Raney-Ni Catalyst Without an External Hydrogen Donor

Finding sustainable resources has always been a strong research due to the current massive consumption of non-renewable fossil fuels on a global scale. Recently, the transformation of renewable biomass into value-added chemicals has become a crucial alternative to solve this problem. Levulinic acid (LA) and glucose are the most significant biomass-derived compounds and γ-valerolactone (GVL) is considered to be the important intermediate of chemicals and fuels. However, the safety and cost of external hydrogen are the main obstacles for the production of GVL from biomass and its derived chemicals by catalytic transfer hydrogenation process. Herein, we introduce the conversion of LA and glucose-derived LA into GVL without an external hydrogen donor, respectively. One process is the production of GVL from LA in a maximum yield of 99% at relatively mild conditions (150 oC) for 3 h with hydrogen, which is from the decarboxylation reaction of formic acid (FA) in water with Raney Ni. The other process is conversion of glucose into LA and GVL in two steps. More than 50% yield of LA and 67% yield of GVL could be obtained from glucose with 3% HCl solution and Raney Ni.