Zr-decorated hyper-cross-linked polymers for highly selective upgrading of furfural to furfuryl alcohol

Abstract

In the present study, the ultra-large specific surface area Zr-decorated hyper-cross-linked polymers (HP) were firstly developed for the catalytic production of furfuryl alcohol (FOL) from furfural (FAL) using isopropanol as both the hydrogen source and solvent. Comprehensive characterizations were performed to uncover the basic physicochemical properties. The as-prepared Zr/HP showed large specific surface area of ∼1000 m2/g, good dispersion of Zr species, plentiful acidity and basicity. 2.5Zr/HP presented the highest activity in the FAL-to-FOL transformation, wherein 97.4 % FAL conversion and 92.9 % FOL yield were achieved within 2 h at 160 °C. The recycling experiments revealed that the as-fabricated Zr-decorated hyper-cross-linked polymers presented good recyclability without significant loss of reactivity even after two consecutive cycles, owing to the strong interaction between hyper-cross-linked polymers and grafted Zr species. Kinetical analysis verified that the activation energy for transfer hydrogenation of FAL could be lowered to a certain degree, especially in the case of lower Zr loadings. More gratifyingly, the Zr-decorated hyper-cross-linked polymers were capable of catalyzing other unsaturated compounds with high conversion rates. In addition, the plausible pathway for the FAL-to-FOL transformation over Zr-decorated hyper-cross-linked polymers was proposed.