Enhanced Catalytic Performance of Supported Nano-gold by the Localized Surface Plasmon Resonance for Selective Hydrogenation of Butadiene

During the polymerization of mono-olefins to prepare polymers,impurities such as alkynes and diolefins can poison the polymerization catalyst. Fossil energy driven thermocatalytic selective hydrogenation is the main impurity removal in the industry,which is a high energy consumption and high pollution process. The development of novel green and low-energy reaction pathways is one of the urgent problems in the current industry. Based on the plasmon resonance effect of metal nanoparticles,converting light energy into thermal energy to drive industrial catalytic hydrogenation is a very promising option. In this study,graphene oxide loaded gold(Au)catalysts(Au/GO) were prepared by cationic adsorption method,and the Au loading(mass fraction 0.2%-2%)was adjusted to achieve controllable preparation of Au in the particle size of 10-21 nm. The efficiency of photo-thermal conversion of Au/GO was as high as 88%. Using the selective catalytic hydrogenation of butadiene as a probe reaction,it was found that under 0.2 W/cm(2) illumination conditions,the conversion of butadiene increased and then decreased with increasing loading,and the butene selectivity was above 90%. Particularly,Au/GO-0.5 exhibited high butadiene conversion (99%)and butene selectivity(90%)at a gold loading of 0.5%(particle size ca. 15 nm)and a photothermal conver. sion temperature of 100 degrees C More importantly,the catalyst showed no deactivation trend after 144 h stability test. In addition,the photo-thermal driven catalytic activity developed in this work was improved by a factor of 5 compared to the thermal catalytic reaction under the same conditions. The analysis by in situ X-ray photoelectron spectroscopy (XPS)tests showed that this improvement in catalytic performance was mainly derived from the large number of Au delta+ active sites generated on the excited nanogold surface during the plasma photo-transfer thermal process. This study provides a green and efficient reaction pathway for the selective catalytic hydrogenation of industrial unsaturated olefins.