Design of Highly Active Photocatalytic System for the Removal of NOx

高活性光催化脱硝系统设计

• 批准号: 02044125
• 负责人: ANPO Masakazu
• 金额: $ 0.9万
• 依托单位: University of Osaka Prefecture
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for international Scientific Research
• 财政年份: 1990
• 资助国家: 日本
• 起止时间: 1990 至 无数据
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-02044125/
• 关键词: photocatalysis; NOx decomposition; photocatalytic decomposition; ion-echanged catalyst; copper ion catalyst; ESR measurement; FT-IR measurement; surface active site

Reducing global air pollution caused by NOx and SOx is currently an urgent and serious challenge. Utilization of photocatalytic processes in gas-solid systems also promising. In the present project, we have studied and found that Cu^<2+> ions supported on silica (Cu^<2+>/SiO_2) and Y-Zeolite (Cu^<2+>/Y-Zeolite) prepared by an ion-exchange method are easily reduced to Cu^+ ions when the Cu^<2+>/SiO_2 and Cu^<2+>/Y-Zeolite samples are evacuated at temperatures higher than 573 K and the reduced Cu^+ ions on silica (Cu^+/SiO_2) and Y-Zeolite (Cu^+/Y-Zeolite) catalysts can decompose NO molecules photocatalytically and stoichiometrically into N_2 and O_2 at 275 K.UV irradiation ( 270 nm) of the Cu^+/SiO_2 and Cu^+/Y-Zeolite catalysts in the presence of NO molecules at 275 K was found to lead to the decomposition of NO into N_2 and O_2. Decomposition of NO proceeds linearly with UV irradiation time at 275 K. The major products of NO decomposition were N_2 and O_2 with a minor formation of N_2 … More O and NO_2. These minor products were found to be secondary products of N, O, and NO, and the overall reaction was found to be stoichiometrical. Thus, these results clearly indicate that UV irradiation of the CU^+/SiO_2 catalyst (or Cu^+/Y-Zeolite) in the presence of NO leads to the photocatalytic decomposition of NO into N_2 and O_2 at 275 K.The physicochemical and photochemical properties of Cu^+ ions anchored onto SiO_2 and Y-Zeolite have been investigated by means of ESR measurements of the copper (Cu^<2+>) ions and of NO species adsorbed on the copper ions and dynamic photoluminescence measurements of the excited state of the copper (Cu^+) ions (3d^94s^1 electronic state), as well as product analysis of photodecomposition of NO molecules. These results indicate that the excited state of copper ions (Cu^+ ions) plays a significant role in the photocatalytic decomposition of NO molecules and the photoreaction involves an electron transfer from the excited state of the Cu^+ ion into an anti-bonding orbital of NO molecule within the lifetime of its excited state.Thus, the present results obtained with the Cu^+/SiO_2 and Cu^+/Y-Zeolite catalysts imply the possibility of their utilization as a potentially promising type of photocatalysts for the direct decomposition of NOx into N_2 and O_2 at around normal temperature. Less

减少由NOX和SOX造成的全球空气污染目前是一个紧迫而严重的挑战。气体固体系统中光催化过程的利用也有望。在本项目中，我们研究并发现在二氧化硅（Cu^<2+>/sio_2）和Y-Zeolite（Cu^<2+>/Y-Zeolite）上支持的Cu^<2+>离子通过离子 - exChange方法制备的Y-Zeolite（Cu^<2+>/Y-Zeolite）很容易将Cu^+离子简化为Cu^<2+>/sio__2和cu^2+<2+<2+<2+<2+>高于573 K的温度以及二氧化硅（Cu^+/sio_2）和Y- Zeolite（Cu^+/Y-Zeolite）催化剂的降低的Cu^+离子可以在275 k.uv Iradiation（275 K.uv hiradiation and s 275 k.uv iradiation and c 275 k.uv iradiation of s n _2和o_2）中分解任何分子，均可以分解发现在275 K处的NO分子存在的情况下，Cu^+/Y-Zulite催化剂导致NO分解为N_2和O_2。在275 K处使用UV辐照时间线性地分解。无分解的主要产物是N_2和O_2，次要形成N_2…更多O和NO_2。发现这些次要产物是N，O和NO的次要产物，并且发现整体反应是石化的。这就是这些结果清楚地表明，在没有NO的情况下，Cu^+/siO_2催化剂（或Cu^+/Y-Zeolite）在NO中导致NO导致NO的光催化分解为N_2和O_2在275 K处的N_2和O_2。 （Cu^<2+>）离子和无物种在铜离子上吸附在铜（Cu^+）离子（Cu^+）离子（3D^94S^1电子状态）的激发态的动态光致发光测量以及无分子光分解的产物分析。这些结果表明，铜离子（Cu^+离子）的激发态在无分子的光催化分解中起着重要作用，并且光电反应涉及电子从Cu^+离子激发状态转移到抗粘结轨道中的No分子的抗粘结状态，并在其令人兴奋的状态中与Cu^+/Sio cu^yno cu^+/Sio cu^y+ Cu^+/Y-zyolite催化剂意味着将其用作在正常温度左右将NOX直接分解为N_2和O_2的潜在有前途的光催化剂类型。较少的

项目成果

M. Anpo: "Preparation of Supported Vanadium Oxide by Photochemical Anchoring Method and Photocatalytic Reactions on It" J. Surf. Sci. Jpn.11. 39-44 (1990)

M. Anpo：“光化学锚定法制备负载型氧化钒及其光催化反应”J. Surf。

M. Anpo: Kluwer Academic Pul. (Dordrecht). Photochemical Conversion and Storage of Solar Energy, (1991)

M. Anpo：Kluwer 学术杂志。

T.Fujii,A.Ishii,S.Suzuki,M.Che, M.Anpo: "Photophysics on Solid Surfaces. TimeーResolved Fluorescence Spectra of Pyrene Adsorbed on Calcinated Vycor Glass" Bull.Chem.Soc.,Jpn.,. 63. 2475-2480 (1990)

T.Fujii、A.Ishii、S.Suzuki、M.Che、M.Anpo：“固体表面上的光物理学。吸附在煅烧 Vycor 玻璃上的芘的时间分辨荧光光谱”Bull.Chem.Soc.，Jpn.,。 63.2475-2480（1990）

T.Fujii,Y.Kurihara,A.Ishii,N.Negishi,M.Anpo: "Enhancement of Thermal Stability of Fluorescein Molecules Encapsulated into Silica Gel Networks by SolーGel Method" Chem.Express.5. 917-920 (1990)

T.Fujii、Y.Kurihara、A.Ishii、N.Negishi、M.Anpo：“通过溶胶-凝胶法增强封装到硅胶网络中的荧光素分子的热稳定性”Chem.Express.5（1990） ）

C. Louis, M. Che, M. Anpo: "The Activity and The Properties of Mo=0 Bonds in Mo/SiO_2 Catalysts" Res. Chem. Intermedi.15. 240-257 (1991)

C. Louis、M. Che、M. Anpo：“Mo/SiO_2 催化剂中 Mo=0 键的活性和性质”Res。