Study of γ-valerolactone production from hydrogenation of levulinic acid over nanostructured Pt-hydrotalcite catalysts at low temperature

Hydrogenation of levulinic acid (LA) to γ-valerolactone (GVL) is an important reaction in biomass upgradation to produce value-added chemicals. In this work, we have successfully prepared well dispersed nanocrystalline Pt-HT catalyst and found that this catalyst is showing excellent performance for the levulinic acid hydrogenation to produce GVL. Pt-HT catalyst showed ∼100% conversion with ∼100% selectivity of GVL at low temperature with external hydrogen in a batch reactor in aqueous medium. Different reaction parameters like hydrogen pressure, temperature, reaction time and loading of Pt were studied in detail. The catalyst was successfully reused up to 7 times without any loss of the catalytic activity. The catalyst was characterized by XRD, SEM, HR-TEM, BET, XPS, TPR, TPD and DFT study. It was observed that the highly dispersed metallic Pt is the active species to achieve the good conversion and selectivity of GVL even at room temperature and the catalyst is showing very high stability and recyclability during hydrogenation, making it very promising truly heterogeneous catalyst for practical γ-valerolactone production via hydrogenation of levulinic acid.