Continuous conversion of fructose to 2,5-furandicarboxylic acid by tandem fixed bed system

The direct synthesis of 2,5-furandicarboxylic acid (FDCA) from readily renewable fructose, would provide a cost approach without separation of 5-hydroxymethylfurfural (HMF). The method would realize efficient and continuous production, reduced by-products, without cumbersome HMF separation process, and reduced production costs. In this work, we succeeded in converting fructose directly into FDCA over combined Amberlyst-15 and Pd/Al2O3 in fixed bed reactor. We firstly time, compared One-bed two-catalysts (OBTC), and two-bed two-catalysts (TBTC) system. For the individual merits of the Amberlyst-15 and Pd/Al2O3, the catalytic performance of the combined beds is significantly improved compared with individual one. The high yields of FDCA (48 %) and fructose conversion (100 %) were obtained, respectively. Our one-step continuously method makes the FDCA production much more economical, energy-saved. [Display omitted] •Dehydration catalysts (Amberlyst-15) and oxidation catalysts (Pd/Al2O3) were installed by two tandem fix-bed system.•High yields of FDCA (48 %) at 140 °C and fructose conversion (100 %) at 120 °C were obtained, respectively.•A continuous/direct conversion of fructose into FDCA are achieved firstly time.•This method is savings in energy and time without complicated separation steps.