Selective Transfer Hydrogenation of Biomass-Based Furfural and 5-Hydroxymethylfurfural over Hydrotalcite-Derived Copper Catalysts Using Methanol as a Hydrogen Donor

A series of inexpensive copper-based catalysts, derived from hydrotalcite precursors, were screened for selective transfer hydrogenation of biomass-based furfural (FFR) to furfuryl alcohol (FA) and 2-methyl furan (MF), with methanol as both the solvent and a hydrogen donor. The specific textural characteristics of the prepared catalysts were characterized by various techniques such as X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), thermogravimetric analysis/differential thermal analysis (TGA/DTA), nitrogen physisorption, temperature-programmed desorption in an ammonia atmosphere (NH3-TPD), temperature-programmed reduction in a hydrogen atmosphere (H2-TPR), infrared (IR) spectra of pyridine adsorption, and X-ray photoelectron spectroscopy (XPS). The copper catalyst showed excellent transfer hydrogenation selectivity toward FFR-to-FA transformation by giving a FA yield of 94.0 mol % at 473 K in methanol. Treating the copper catalyst with H2/N2 at 773 K l...