Chunhua Wang,Zhiquan Yu,Yuhao Yang,Zhichao Sun,Yao Wang,Chuan Shi,Ying-Ya Liu,Anjie Wang,Karen Leus,Pascal Van Der Voort
Upgrading furfural (FAL) to cyclopentanone (CPO) is of great importance for the synthesis of high-value chemicals and biomass utilization. The hydrogenative ring-rearrangement of FAL is catalyzed by metal-acid bifunctional catalysts. The Lewis acidity is a key factor in promoting the rearrangement of furan rings and achieving a high selectivity to CPO. In this work, highly dispersed Pd nanoparticles were successfully encapsulated into the cavities of a Zr based MOF, UiO-66-NO2, by impregnation using a double-solvent method (DSM) followed by H2reduction. The obtained Pd/UiO-66-NO2catalyst showed a significantly better catalytic performance in the aforementioned reaction than the Pd/UiO-66 catalyst due to the higher Lewis acidity of the support. Moreover, by using a thermal treatment. The Lewis acidity can be further increased through the creating of missing-linker defects. The resulting defective Pd/UiO-66-NO2exhibited the highest CPO selectivity and FAL conversion of 96.6% and 98.9%, respectively. In addition, the catalyst was able to maintain a high activity and stability after four consecutive runs. The current study not only provides an efficient catalytic reaction system for the hydrogenative ring-rearrangement of furfural to cyclopentanone but also emphasizes the importance of defect sites.Keywords:Pd/UiO-66-NO2;furfural;hydrogenative ring-rearrangement;cyclopentanone;double-solvent method
The hydrogenative rearrangement of biomass-derived furfural offers a sustainable pathway to produce cyclopentanol (CPL) and cyclopentanone (CPO), which are traditionally obtained from fossil resources. Achieving selective synthesis of either product requires precise control over catalyst electronic structure and adsorption behavior, yet it still remains challenging. Herein, we report that both doping and tuning the spatial distance between Pt clusters effectively regulate the d -band center of active sites, enabling selective synthesis of CPO and CPL with high yields of 97.2 % and 96.0 %, respectively. Mechanistic studies suggest that reducing the spatial distance between Pt nanoclusters elevates the d -band center, thereby reducing the occupancy of antibonding states and strengthening the Pt-O bond between Pt and CPO, thus favoring CPL formation. By contrast, doping Pt with NiP lowers the d -band center, thus weakening CPO adsorption and promoting its selective synthesis. These results highlight d -band center regulation as a promising strategy for achieving selective hydrogenation.