Selective hydrogenation of furfural to tetrahydrofurfuryl alcohol over a Rh-loaded carbon catalyst in aqueous solution under mild conditions

We describe the selective hydrogenation of furfural (FAL) into tetrahydrofurfuryl alcohol (THFA) under mild conditions (30 °C) in aqueous media using an Rh-loaded carbon (Rh/C) catalyst in a one-pot fashion. In FAL hydrogenation, the Rh/C catalyst showed a high THFA yield (92%) with 93% selectivity in aqueous media within 12 h, whereas the use of a dimethylacetamide (DMA) solvent system resulted in a 95% THFA yield within 32 h at 30 °C. The study of the effect of the solvent on FAL hydrogenation reveals that polar solvents showed higher THFA yields than a toluene solvent. The Rh/C catalyst used in this study exhibited higher activity compared to Ru/C, Pd/C, Ni/C derived from Ni-based metal-organic framework (Ni-MOF), and Ni-loaded carbon black (Ni/CB) catalysts in FAL-to-THFA hydrogenation. The Rh/C catalyst is characterized in detail using various characterization techniques such as TEM, XRD, N₂-adsorption-desorption, XPS, and ICP-OES to understand its physicochemical properties. The Rh/C catalyst shows similar high THFA yields in the recycling experiment of FAL hydrogenation under ambient conditions.