Enhanced activity of Ru-Ir nanoparticles over SiC for hydrogenation of levulinic acid at room-temperature

Abstract The hydrogenation of levulinic acid (LA) to γ-valerolactone (GVL) under mild condition is a promising but challenging process. Herein, SiC supported Ru-Ir bimetallic catalyst exhibit enhanced catalytic activity for aqueous hydrogenation of LA into GVL under mild conditions. Comparing with monometallic Ir3/SiC and Ru3/SiC, the conversion of LA over bimetallic Ru0.5-Ir2.5/SiC catalyst increase from 51.2 % and 45.9% to 100% at 25 °C and 0.2 MPa of H2 pressure. The enhanced catalytic activity of Ru0.5-Ir2.5/SiC catalyst originates from the electronic synergistic effect among Ru, Ir and SiC. Due to the electron transfer, electron-richened Ir nanoparticles show stronger ability for H2 dissociation, and the SiC surface produces more active sites to accommodate hydrogen species that spill over from Ir and Ru. The adsorption and hydrogenation of LA molecules occur on the surface of SiC.