Continuous flow conversion of alkyl levulinates into γ-valerolactone in the presence of Ru/C as catalyst

The present work explored a catalytic transfer hydrogenation process with several supported noble metal on carbon as catalysts for the production of gamma-valerolactone (GVL) from methyl levulinates (ML) in iso-propanol (2-PrOH) and the performance of the commercial 5%Ru/C in continuous flow were investigated, GVL yields up to 83% at 150 degrees C (40 bar) using a high load (0.4 M ML) feed at 0.8 mL/min flow rate. The catalyst productivity (Pr) equal to 0.99 mol g(-1)h(-1). Methyl 4-hydroxypentanoate (MHP) were produced as major side product in lower amounts in continuous flow mode. Long-term (9 h) catalyst stability experiment showed good stability under optimum condition. The yield of GVL obtained from ethyl levulinate, butanol levuliante and levulinate acid were ca 21%, 54% and 26% less than ML in 2-PrOH and Pr were 0.43, 0.73 and 0.48 less respectively. There is no obvious hydrogenation process when changed 2-PrOH to ethanol and 1-butanol.