Hydrogenation of Furfural over Ruthenium Catalysts Supported on Porous Aromatic Frameworks

The paper describes an investigation into hydrogenation of furfural over ruthenium catalysts supported on porous aromatic frameworks. The supports were designated as PAF-30-SO₃H, PAF-30-NH₂, and PAF-30. The synthesized catalysts were tested in furfural hydrogenation carried out in water and in tetrahydrofuran (with a concentration of 10 wt %) at 90–250°C and a hydrogen pressure of 3 MPa. Although the highest furfural conversion (96%) was achieved in the case of its hydrogenation in water at 250°C over Ru-PAF-30, these conditions did not favor product selectivity. The reaction products mainly consisted of furfuryl alcohol, tetrahydrofurfuryl alcohol, and cyclopentanone. The highest yield of cyclopentanone, 71% (with 80% conversion and 89% selectivity) was observed in furfural hydrogenation over Ru-PAF-30 at 200°C, whereas the conditions optimal for selective hydrogenation of furfural into furfuryl alcohol were found to include either tetrahydrofuran as a solvent or water as a solvent and low temperatures (90–150°C).