| Phenol is one of the most significant chemical materials and plays an important role in chemical industry. While the traditional synthesis processes of phenol have a lot of disadvantages, such as terrible atom economics and causing much pollution which are in the opposite direction with "green chemistry" development trend. Therefore, researcher have done a lot of work to find new approaches to synthesize phenol from benzene. Photocatalysis has attracted much attention for its high efficiency, energy conservation, and environmentally friendly. In this thesis, we studied the applications of TiO2 based photocatalysts in oxiadations of benzene to phenol, TiO2 nanoparticles were adopted to be the main catalysts and Cu-Ni alloy to be the cocatalysts in the photocatalysts.Firstly, The Cu co-modified TiO2 nanoparticles photocatalyst was prepared by a simple "soak-deoxidize " process using TiO2 nanoparticles as main catalyst. On the base, we investigated the application of TiO-Cu on the direct oxidation benzene to phenol with photocatalytic process. The results of this study was disappointing, the Cu co-modified TiO2 nanoparticles photocatalyst was no visible light activity to the process of hydroxylation benzene to phenol.Second, we used TiO2 nanoparticles as main catalyst, CuO loaded on the surface of TiO2 by a an impregnation procedure and then by a thermal decomposition process. And then we builded a reaction system with H2O2 as an oxidant and acetonitrile as the solvent. The results showed that we obtained the phenol from benzene successfully under the visible light irradiation, the yield of phenol was 5.40%.Third, we prepared the surface modifications TiO2 used Cu-Ni alloy as the cocatalyst. The catalytic activity of the TiO2-Cu-Ni alloy was researched comprehensive. Due to the synergy between copper and nickel, the visible light catalytic activity of TiO2 had greatly improving, the most yield of phenol could reach 18.49%. |
PDF Full Text Request