2,5-Furandicarboxylic acid (FDCA), a bio-based diacid with a rigid ring, has a similar structure to petroleum-based terephthalic acid. Its co-polyester with ethylene glycol has excellent performance in terms of thermal and mechanical properties. Herein, an Au/CeO2-rod catalyst with rich oxygen vacancies was developed to achieve the efficient oxidation of 2,5-bis(hydroxymethyl)furan (BHMF) to FDCA with a 92 % yield under mild conditions, with the addition of 4 equivalents of Na2CO3 at 80℃ under 2 MPa O2 for 6 h. The large specific surface area of CeO2-rod is beneficial for better dispersion of Au nanoparticles. Meanwhile, the high activity of Au/CeO2-rod can be attributed to that the rod-shaped CeO2 exposed more active (100) facets, resulting in strong metal-support interaction between Au nanoparticles and CeO2-rod. This could generate more Au species with oxidized state and more oxygen vacancies, thus promoting the reactant adsorption and oxygen activation and enhancing the final oxidation activity. The oxidation of 5-hydroxymethyl-2-furancarboxylic acid to FDCA was determined as the rate-determining step in the oxidation of BHMF over the Au/CeO2 catalyst.
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