Catalytic Hydrogenation of Furfural over UiO-66-NH₂-derived Ru-based Catalysts: Precursor Coordination Structure for Enhanced Catalysis

The -NH2 in UiO-66-NH2 was functionally modified with 2-pyridinecarboxaldehyde to form Schiff base UiO-66-Pyr, and hollow nitrogen-doped porous carbon-ZrO2 supported Ru (Ru/NC-ZrO2) was prepared from Ru3+-coordinated UiO-66-Pyr-Ru. Then the furfural hydrogenation performance of the product was investigated. Compared with single-tooth-coordinated UiO-66-NH2, the 2-tooth-coordinated UiO-66-Pyr can improve the stability of Ru3+ coordination and thereby increase the Ru loading and dispersity in the Ru/NC-ZrO2, showing high furfural hydrogenation activity. The direct hydrogenation with hydrogen as the hydrogen source and the transfer hydrogenation with isopropanol as the hydrogen donor was determined by the furfural hydrogenation of Ru/NC-ZrO2 under hydrogen or nitrogen.