Production of γ-valerolactone from levulinic acid over a Ru/C catalyst using formic acid as the sole hydrogen source.

Conversion of levulinic acid (LA) to γ-valerolactone (GVL) over a ruthenium-carbon (Ru/C) catalyst using formic acid (FA) as the sole hydrogen source in cellulose hydrolysis process was investigated. The reaction was accelerated using Ru(5wt%)/C as the catalyst and by adding triethylamine. The highest LA conversion (87.26%) and GVL yield (80.75%) were obtained using 10g/mol (LA) catalyst and 150mL/mol (LA) triethylamine at 160°C for 180min. In this reaction, the hydrogenation process can only be accomplished in the presence of FA, which is the byproduct of LA production from cellulose hydrolysis. The application of this new route not only improves the economy of the process, but also avoids the energy-costly separation of LA from the LA and FA aqueous mixture. A new reaction pathway for the conversion of LA and FA into GVL over Ru/C with triethylamine was proposed.