Industrial & Engineering Chemistry Research, Vol.58, No.29, 13122-13132, 2019
Self-Developed Fabrication of Manganese Oxides Microtubes with Efficient Catalytic Performance for the Selective Oxidation of 5-Hydroxymethylfurfural
The development of green catalytic processes from biomass-derived feedstock such as 5-hydroxymethylfurfural (HMF) to valuable chemicals is a hot topic in which the facile synthesis of heterogeneous catalyst and molecular oxygen as the oxidant are desired. In this work, manganese oxide (MnOx) microtubes were prepared by a facile solvothermal method via in situ self-development, where chemical conversion coupled with physical Ostwald ripening occurred. The results showed that MnOx microtubes could be used as an efficient catalyst for the selective aerobic oxidation of HMF to 2,5-diformylfuran (DFF). Various reaction parameters have been investigated and DFF was obtained with a high selectivity of 100% under the reaction conditions of 90 degrees C, 8.0 bar O-2, and N,N-dimethylformamide as solvent. Moreover, kinetic parameters revealed that the reaction fitted the first order equation corresponding to HMF. In particular, it was demonstrated that the activation energy was low with an 11.80 kcal/mol in comparison with reported non-noble catalysts, thus the reaction could be performed under a relatively low reaction temperature. Furthermore, the catalyst could be easily recoverable and reusable after several times without any significant loss, suggesting its excellent reusability and stability.