Catalysis Letters, Vol.142, No.8, 1011-1019, 2012
Gold Catalysts for Selective Aerobic Oxidation of the Lignan Hydroxymatairesinol to Oxomatairesinol: Catalyst Deactivation and Regeneration
The lignan oxomatairesinol was synthesized from the biomass-derived lignan hydroxymatairesinol via selective aerobic oxidation over a heterogeneous gold catalyst. The catalyst was prepared by direct ion-exchange and characterized by XRD, TEM and ICP-OES methods. The reaction was carried out at 70 A degrees C and atmospheric pressure in a semi-batch reactor. To reveal the origin of catalyst deactivation, spent catalysts were studied by TEM, XRD, nitrogen physisorption, ICP-OES, TPO, and DSC-TGA techniques. Several regeneration procedures were applied-extraction by several solvents and calcinations in the oxidizing atmosphere. The former one was found to be the most effective way for the catalyst regeneration.
Keywords:Gold catalysts;Selective oxidation;Biomass;Lignans;Oxomatairesinol;Hydroxymatairesinol;Catalyst deactivation