Liquid-Phase Selective Hydrogenation of Furfural to Furfuryl Alcohol over Ferromagnetic Element (Fe, Co, Ni, Nd)-Promoted Pt Catalysts Supported on Activated Carbon

Ferromagnetic element (x = Fe, Co, Ni, and Nd)-promoted Pt/AC catalysts were prepared by co-impregnation method or physical mixing and tested in the liquid-phase hydrogenation of furfural to furfuryl alcohol (FA) under mild conditions (50 °C and 20 bar H2) using water and methanol as the solvent. Among the various catalysts studied, the 0.15FePt/AC exhibited complete conversion of furfural with an FA selectivity of 74% after only 1 h of reaction time in water. The promotional effect of the bimetallic catalysts became less pronounced when methanol was used as the solvent and a 2-furaldehyde dimethyl acetal solvent product was formed. The superior catalyst performances were correlated with the higher Pt dispersion, the presence of low coordination Pt sites, and the strong Pt–Fe interaction as characterized by X-ray diffraction, H2 temperature-programmed reduction (H2-TPR), N2 physisorption, and infrared spectroscopy of the adsorbed CO (CO-IR). However, to simply use a magnet for catalyst separation, 0.5 wt% Fe was the minimum Fe loading on the Pt/AC. The 0.5FePt/AC still exhibited good magnetic properties after the third consecutive runs.