A novel complex nano-structured Au@TiO2 gold catalyst has been prepared. Au precursor could be transformed into Au@TiO2/MCM-22 with the complex nano-structured using two different methods. Samples were characterized b...A novel complex nano-structured Au@TiO2 gold catalyst has been prepared. Au precursor could be transformed into Au@TiO2/MCM-22 with the complex nano-structured using two different methods. Samples were characterized by XRD, FT-IR, UV-vis, TEM, ICP-AES and N2 adsorption-desorption. It is found that gold was anchored on the TiO2/MCM-22 as small size and uniform particles with the average diameters in the range of 5 - 9 nm. Catalytic results show that such nano-gold catalysts display excellent catalytic performance for cyclohexane oxidation. Au@TiO2/MCM-22 catalyst with the gold content of 0.5 wt% exhibits extremely exceptionally catalytic activity (12.81%) and high turnover frequency (52,121 h-1), which may be ascribed to the synergistic effects of Au and TiO2 in the complex nano-structured catalyst Au@TiO2/ MCM-22. Because of the strong metal support interaction, aggregation of active sites (Au nanoparticles) during the oxidation reaction is effectively prohibited and the catalytic activity is essentially retained.展开更多
Chinese steel industry has made significant progress on reducing fresh water consumption and CO_2/SO_2/COD（ chemical oxygen demand） /dust emissions,and improving comprehensive utilization of solid waste. Some steel ...Chinese steel industry has made significant progress on reducing fresh water consumption and CO_2/SO_2/COD（ chemical oxygen demand） /dust emissions,and improving comprehensive utilization of solid waste. Some steel companies have become topped worldwide. However,due to the large output quantity of crude steel,the whole steel industry is still a huge source of pollutants. At present,environmental protection standards are encountering challenges of lack of technical support,taxation policy and other issues. Steel industry is currently facing enormous environmental pressure. The development trends of environmental protection technologies were studied by summarizing different development stages. To realize the development targets,the industry needs to carry out its research with independent intellectual property rights,develop comprehensive management systems and establish ecological chain with other industries. This can not only raise the level of environmental protection in a broader range,but also improve the energy efficiency of iron and steel plants and increase added value of waste utilization. Finally,23 environmental protection technologies were proposed and 4 new environmental protection practices were studied.展开更多
文摘A novel complex nano-structured Au@TiO2 gold catalyst has been prepared. Au precursor could be transformed into Au@TiO2/MCM-22 with the complex nano-structured using two different methods. Samples were characterized by XRD, FT-IR, UV-vis, TEM, ICP-AES and N2 adsorption-desorption. It is found that gold was anchored on the TiO2/MCM-22 as small size and uniform particles with the average diameters in the range of 5 - 9 nm. Catalytic results show that such nano-gold catalysts display excellent catalytic performance for cyclohexane oxidation. Au@TiO2/MCM-22 catalyst with the gold content of 0.5 wt% exhibits extremely exceptionally catalytic activity (12.81%) and high turnover frequency (52,121 h-1), which may be ascribed to the synergistic effects of Au and TiO2 in the complex nano-structured catalyst Au@TiO2/ MCM-22. Because of the strong metal support interaction, aggregation of active sites (Au nanoparticles) during the oxidation reaction is effectively prohibited and the catalytic activity is essentially retained.
基金supported by National Natural Science Foundation of China(Grants No.51234003)
文摘Chinese steel industry has made significant progress on reducing fresh water consumption and CO_2/SO_2/COD（ chemical oxygen demand） /dust emissions,and improving comprehensive utilization of solid waste. Some steel companies have become topped worldwide. However,due to the large output quantity of crude steel,the whole steel industry is still a huge source of pollutants. At present,environmental protection standards are encountering challenges of lack of technical support,taxation policy and other issues. Steel industry is currently facing enormous environmental pressure. The development trends of environmental protection technologies were studied by summarizing different development stages. To realize the development targets,the industry needs to carry out its research with independent intellectual property rights,develop comprehensive management systems and establish ecological chain with other industries. This can not only raise the level of environmental protection in a broader range,but also improve the energy efficiency of iron and steel plants and increase added value of waste utilization. Finally,23 environmental protection technologies were proposed and 4 new environmental protection practices were studied.
