Insights into the Oxidative Esterification of 5-Hydroxymethylfurfural Toward Furan-2,5-dimethylcarboxylate over MnO@Co-CN Catalyst

Graphical In this study, a straightforward coprecipitation method was employed to synthesize the bimetallic catalyst MnO@Co-CN, which demonstrates high efficiency in catalyzing the direct oxidative esterification of HMF to produce FDMC with a yield reaching 90.3%. The synergistic interactions between the dual metals during the reaction significantly enhance the catalytic performance for optimal oxidative esterification. As a versatile platform molecule derived from biomass, 5-hydroxymethylfurfural (HMF) has the potential to be transformed into a variety of chemicals. Of these, furan-2,5-dimethylcarboxylate (FDMC) stands out as an excellent precursor for the synthesis of poly(ethylene furandicarboxylate) (PEF), a polymer with broad applications in the production of various polymeric materials. However, a majority of studies have focused on the use of noble metal catalysts to achieve the direct oxidative esterification of HMF for the production of FDMC. Given the scarcity and high cost of noble metal catalysts, there is a pressing need to develop non-noble metal catalysts to efficiently facilitate the direct oxidative esterification of HMF. Accordingly, a bimetallic catalyst, MnO@Co-CN, was prepared in this paper by a simple coprecipitation method, and a 90.3% FDMC yield was obtained under optimal conditions. The findings revealed that in the oxidative esterification of HMF, MnO x predominantly adsorbs the reactants onto the catalyst surface, whereas CoO x is primarily responsible for the oxidation. The synergistic interaction between Mn and Co enhances the catalytic performance, leading to the superior oxidative esterification outcomes. This work offers a cost-effective, scalable method for FDMC synthesis, highlighting potential for industrial applications.