Cu/CuO_x@C for efficient selective transfer hydrogenation of furfural to furfuryl alcohol with formic acid

Abstract

Background Catalytic transfer hydrogenation has been increasingly employed as an effective and safe method for biomass upgrading; however, relying on biomass‐derived formic acid (FA) as hydrogen source has rarely been studied, especially in the production of furfuryl alcohol (FOL) from biomass‐derived furfural (FF) via selective hydrogenation, which is challenging due to diverse unsaturated groups. Herein, in situ encapsulation and stabilization of Cu/CuOx in a porous carbon matrix (Cu/CuOx@C) was reported for the first time and applied in the hydrogenation of FF to FOL with FA. Results Various analytical techniques were used to characterize the effect of pyrolysis temperature on Cu/CuOx@C, since the temperature can be adjusted to control the reduction of the catalyst to give different Cu0/Cun+ ratios. The optimal catalyst Cu/CuOx@C‐450 gave a 99.1% FF conversion and 98% FOL selectivity under suitable reaction conditions, exhibiting excellent activity that was even better than those of noble metal catalysts. Further, density functional theory calculations were used to reveal the effect of Cu species on FA decomposition and final catalytic performance. Conclusion The catalytic activity of Cu/CuOx@C was influenced by the pyrolysis temperature of the catalyst precursor, and its good performance was mainly attributed to a high dispersion of accessible catalytic Cu/CuOx nanoparticles on the porous carbon and to an appropriate Cu0/Cun+ ratio. © 2022 Society of Chemical Industry (SCI).

Recent progress of heterogeneous catalysts for transfer hydrogenation under the background of carbon neutrality

“…Under appropriate reaction conditions, the Cu/CuO x @C-450 catalyst showed a high furfural conversion of 99.1% with a 98% furfuryl alcohol selectivity due to the high dispersion of Cu/CuO x NPs and the suitable Cu 0 /Cu n + ratio. 164 Lomate et al found the Cu-SiO 2 catalyst showed a higher levulinic acid conversion and valerolactone selectivity when using formic acid as a hydrogen source compared to that of only the SiO 2 support. The key to the high activity and selectivity lies in the strong interaction of some copper oxide monomers with the support and the binding of more acid sites in Cu-SiO 2 .…”

Mild and selective transfer hydrogenation of biomass-derived furfural to furfuryl alcohol over Cu/ZnO/Al2O3 with methanediol as the hydrogen donor

“…14 Wang et al achieved 99% FF conversion and 97% FFA selectivity over a Cu/CuOx@C catalyst with the same temperature and hydrogen source that Lin and co-workers used. 38 Kawi and Srifa reported a CTH of FF over a CuAl catalyst using 2-propanol as the H 2 donor. FF was fully converted at 180 °C with a maximum FFA selectivity of 92.8%.…”