Surface species of supported ruthenium catalysts in selective hydrogenation of levulinic esters for bio-refinery application

Abstract

Several supported noble metal catalysts were screened for the hydrogenation of methyl levulinate to c-valerolactone (GVL). Among these catalysts 5 % Ru/C showed the highest conversion of 95 % of methyl levulinate with 91 % selectivity to GVL. A detailed characterization was carried out using TPR, XRD, XPS and BET techniques. XPS studies revealed that higher extent of Ru0 species in case of carbon supported Ru was responsible for its higher hydrogenation activity as compared to Ru on other supports. Effect of process parameters such as temperature, H 2 pressure, catalyst and substrate concentration and metal loading on methyl LA conversion and selectivity to GVL also has been studied. 5 % Ru/C catalyst was found to be stable up to five reuses. © 2012 Springer Science+Business Media, LLC.