| Abstract: | Recently, gold nanoparticles attracted an increased attention due to unusual and somewhat unexpected catalytic properties especially pronounced in the oxidation of some organic compounds. Gold nanoparticles, which was immobilized on powder Norit® activated carbon as a support (1.0 wt % Au101/AC) exhibited high activity and selectivity for benzyl alcohol oxidation particularly with the gold catalysts subjected to a specific type of activation and temperature. The interaction between Au101 particles and its support was studied by measuring the catalytic activity and selectivity as a function of activation procedure. The first method included washing with a solvent (i.e., toluene) at elevated temperature, and/or followed by heat treatments at mild temperatures (i.e., 100 and 200°C for 3 h). The highest catalytic activity of benzyl alcohol oxidation was however obtained when gold catalysts were pre-washed with hot toluene at 100°C for 2 h followed by thermal treatment under vacuum. In these cases, the gold core diameters was ∼3.5 nm. In a number of experiments, the reaction time was 3 h, whereas in other runs it was extended to 24 h. The conversion level of benzyl alcohol oxidation was affected by the type of activation and its temperature related to the gold particles size. |
