Rational development of an electron-rich platinum nanocatalyst for the oxidation of 5-hydroxymethylfurfural into 2,5-furandicarboxilic acid under mild conditions
Valorization of lignocellulosic biomass for the production of commodity chemicals using various chemical methods continues to attract considerable attention. A wide and diverse range of different chemicals can be obtained from biomass and many different downstream pathways are currently under development. The conversion of various cellulosic derivatives such as glucose and fructose to 5-hydroxymethylfurfural (HMF) has been identified as a key route. However, since HMF is intrinsically unstable, its transformation to other compounds is required. In this context, 2,5-furandicarboxylic acid (FDCA) is a leading candidate, as it has the potential to replace terephthalic acid – the main component of polyethylene terephthalate (PET). Based on the broad usage of FDCA as platform chemical, it was listed as one of the 12 key sugar-based platform chemicals for the production of bio-based chemicals and materials. Herein we present the catalytic oxidation of HMF into FDCA using Pt nanoparticles with molecular oxygen. A mechanistic investigation involving kinetic modeling and a correlation of the nanoparticle size with the different step was undertaken. Based on this analysis we hypothesized that a highly electron rich nanoparticle surface would enhance catalytic activity. Subsequent manipulation of the nanoparticle surface by the introduction of an ionic polymer stabilizer afforded surface electron-rich Pt nanoparticles that catalyze the transformation of HMF to FDCA under mild conditions in the absence of additives. The catalytic system is reasonably benign as molecular oxygen is employed as the oxidant and the process operates in water.
Record created on 2014-10-31, modified on 2016-08-09