(180d) Aqueous Phase Hydrogenation of Furfural Using Silica Supported Ultrasmall Bimetallic Catalysts

Furfural is one of the key platform chemicals in the biomass conversion process. Its transformation to high-value products and treatment for bio-oil stability using heterogenous catalyst remains a crucial step for its commercialization. In this study, silica-supported bimetallic catalyst (PdX/SiO₂, X=Cu, Co, Ni) of varying metal ratios (3:2, 1:1, and 2:3) were synthesized using the method of simultaneous strong electrostatic adsorption (co-SEA) to produce ultrasmall nanoparticles for the aqueous phase hydrogenation of furfural. The prepared catalysts were characterized using powder x-ray diffraction (XRD), temperature-programmed reduction (TPR), X-ray photoelectron spectroscopy (XPS), and induced coupled plasma-optical emission spectroscopy (ICP-OES). The catalytic performance was investigated in batch mode using a 100 mL autoclave reactor operated at 150 °C, 430 psi, and 1000 rpm. Liquid samples obtained during the reaction were analyzed using gas chromatograpy. Two competing reaction paths in the presence of water were observed arising from the furfural ring opening to form levulinaldehyde and further ring-rearrangement to form cyclopentanone. Catalyst activity and selectivity were affected by the metal ratio and the secondary metal alloyed with palladium. The general trend shows higher selectivity towards levulinaldehyde at a much lower Pd:X ratio. Post-reaction catalyst characterization and catalyst recyclability will be made. To our knowledge, this is the first report on the formation of levulinaldehyde using silica-supported Pd-based catalyst prepared by co-SEA.