Potassium Carbonate (K2CO3)-Assisted Copper-Catalyzed Liquid-Phase Hydrogenation of Furfural: Striking Promotion Synergy Enables a Superior High Furfuryl Alcohol Yield at Mild Reaction Conditions

In the hydrogenation of furfural over a copper catalyst, the sluggish kinetics of hydrogen adsorption strongly constrains the overall activity, especially at mild temperatures (≤100 °C). To resolve this issue, we reported an efficient strategy of K2CO3 assisting the CuO#TiO2 catalyst for the liquid-phase hydrogenation of furfural. Assisted by the K2CO3, the CuO#TiO2 acquired a high furfuryl alcohol productivity of 24.2 molFOL/(molCu h) at 100 °C and 1.4 MPa, nearly 4-fold higher than the single CuO#TiO2 did, representing the top catalytic performance among the most state-of-the-art reports so far. Moreover, analogous promotion synergy is available in commercial copper nanoparticles and other substrates with excellent activity and selectivity, demonstrating its broad applicability. Catalyst structure characterizations and controlled experiments have unveiled that the assistance of K2CO3 served a prominent dual-functional role, (i) boosting the in situ generation of surface copper active sites and (ii) promoting the gaseous hydrogen dissolution in ethanol media. Both contributions enabled smoothed overall hydrogen dissociative adsorption kinetics, realizing a striking enhanced hydrogenation activity under a mild reaction. This K2CO3-induced promotion synergy discovery can offer a simplified but efficient strategy for copper-catalyzed biomass valorization.