Selective Oxidation of Biomass‐Derived 5‐Hydroxymethylfurfural into 2,5‐Diformylfuran over the Oxygen‐Vacancy‐Rich Ru/MnO₂ Catalyst

Due to the depletion of traditional fossil resources and the increasing environmental problems, the utilization of sustainable biomass resources has become imperative. The selective oxidation of biomass‐derived 5‐hydroxymethylfurfural (HMF) to 2,5‐diformylfuran (DFF) has attracted much attention in recent years. However, the large‐scale production of DFF remains a challenge given the low dosage of HMF in previous research. In this contribution, a desirable DFF yield of 90.5% is obtained from concentrated HMF (130 °C, 2.0 MPa oxygen, 8 h) over the prepared Ru/MnO 2 catalyst with abundant oxygen vacancies ( O V ). The Ru/MnO 2 catalyst with high O V exhibits a weak MnO bond intensity resulting in high lattice oxygen ( O L ) reactivity, which promotes a high catalytic activity of HMF oxidation. Reusability studies show that the Ru/MnO 2 catalyst is stable and reusable. Furthermore, the direct production of DFF from fructose is also successfully realized via two consecutive steps, leading to a cost‐efficient oxidation of HMF solution and facilitating the industrial production of DFF. This research provides profound insights into the selective oxidation of HMF to DFF, thereby fostering further investigations into the conversion of fructose into high‐value chemicals.