Porous Hafnium-Containing Acid/Base Bifunctional Catalysts for Efficient Upgrading of Bio-Derived Aldehydes

Novel organic-inorganic hybrids were synthesized by using HfCl4 and organic ligand 1H-pyrrole-2, 5-dicarboxylic acid (PDCA) via a simple hydrothermal method. The as-prepared Hf-PDCA were characterized by various techniques, such as electron microscope, N2 adsorption/desorption, and X-ray photoelectron spectroscopy. Among them, the porous and nitrogen-containing Hf-PDCA as heterogeneous acid/base bifunctional catalyst was then applied to the catalytic hydrogenation of furfural to produce furfuryl alcohol (FFA). It exhibited excellent catalytic performance, with high conversion (98.8%) and selectivity (98.5%) by using 2-propanol as hydrogen source under a relatively mild condition. Moreover, the Hf-PDCA has strong stability and durability, and can be recovered after the catalyst reaction. In addition, the Hf-PDCA as catalyst can be extended to fabricate corresponding alcohols by catalytic conversion of other biomass derived aldehydes.