Catalytic Oxidation Of 5-hydroxymethylfurfural To 2,5-diformylfuran By Heterogeneous Catalyst

Due to the low price of the biomass resources,it is expected to be a substitute for fossil fuels in the future.As an important oxidation product of5-hydroxymethylfurfural?5-HMF?,2,5-diformylfuran?DFF?has been an important application in medicine,polymer materials and fine chemicals.Therefore,much effort has been paid to study how to transform 5-hydroxymethylfurfural?5-HMF?into2,5-diformylfuran?DFF?.In this paper,manganese carbonate was prepared by coprecipitation method,and the catalyst was activated by high-temperature calcination to catalyze the oxidation of5-hydroxymethylfurfural to 2,5-diformylfuran.The properties and morphology of the catalyst were measured by SEM,XRD,TGA,N₂ adsorption and XPS.The results showed that the synthesized catalyst was a spherical structure formed by sheet-like stacking.Meanwhile,XRD and XPS showed that the catalytic activity center after calcination was still manganese carbonate.To achieve an optimum DFF yield,different reaction conditions including reaction temperature,reaction time,catalyst amount and solvents were investigated.As a result,the highest DFF yield of 86.9%was obtained at 120? under atmospheric oxygen pressure after 6 h in 4 mL DMSO.Finally,MnCO₃ can be used at least 5 times with considerable stability.The homogeneous phosphotungstic acid was converted into a heterogeneous catalyst by MIL-100?Fe?.HPMo@MIL-100?Fe?has been synthesized for catalytic conversion of 5-hydroxymethylfurfural?5-HMF?to 2,5-diformylfuran?DFF?.The catalyst was characterized by XPS,XRD,FT-IR and N₂ adsorption.A series of characterization methods demonstrated that phosphomolybdic acid was successfully encapsulated in MIL-100?Fe?.In addition,the reaction time,temperature,catalyst amount,solvents have an important impact on the oxidation of5-hydroxymethylfurfural?5-HMF?.As a result,the highest DFF yield of 79.2%was obtained at 120? under atmospheric oxygen pressure after 12 h in 4 m L DMSO.In addition,HPMo@MIL-100?Fe?can be used at least 5 times with considerable stability.