Base‐free Air Oxidation of Chitin‐derived Glucosamine to Glucosaminic Acid by Zinc Oxide‐supported Gold Nanoparticles
Yue Zheng, Di Xu, Lei Zhang, Xi Chen
Abstract
Abstract In this study, glucosaminic acid (GlcNA) was produced with the highest yield of ∼85% from chitin biomass‐derived glucosamine (GlcN) at 35 °C under atmospheric air in water, by using zinc oxide‐supported gold nanoparticles (Au/ZnO). The Au/ZnO catalyst prepared by the deposition‐precipitation (DP) method displayed remarkably superior catalytic performance to that prepared by the deposition‐reduction (DR) method, which led to >2‐fold enhancement in product yield. A lower apparent activation energy (E a ) was observed over the Au/ZnO (DP) for GlcNA formation compared with the Au/ZnO (DR) catalyst. Based on control tests and structural characterizations, the average particle size of Au nanoparticles (NPs) and the surface oxygen vacancy (O V ) sites were the crucial factors on the catalytic activity. The work puts forward a green, mild and efficient approach to synthesize valuable amino acid from ocean‐based chitin biomass resources with air as the oxidant, adding on new possibilities of chitin biorefinery.