|
Heteropoly compounds as a class of inorganic cluster compounds , because of its unique structure , the diverse nature of the field of industrial catalysis, materials science , pharmacy and biology has a wide range of important applications . However heteropoly compounds having a relatively small specific surface area , surface acid oxidation or light oxidation activity is less drawbacks, affecting its catalytic activity , however, if the heteropoly compound supported on a carrier , not only can increase its corresponding ratio surface area, improving its catalytic performance , but also to make a homogeneous catalytic reaction heterogenized , easy separation of the product , the increase in the application can be repetitive, recyclability , etc. . TiO 2 carrier, were prepared by impregnation method PW 12 < / sub > / the TiO 2 < / sub> , the SiW 12 < / sub > / the TiO 2 the SiW 11 M / TiO and 2 (M = Mn , Co, Cu , Ni ) , IR, UV spectra , X - ray powder diffraction characterization means a the catalyst load heteropolyanion Keggin structure remains . Measured the specific surface area and pore structure of the catalyst prepared by N2 adsorption - desorption . Supported acids and salts of the specific surface area and pore structure were compared , to analyze its influence on the catalytic activity , and to study the thermal stability and pyrolysis kinetics . Methylene blue to simulate organic dye pollutants using PW 12 / TiO 2 , the SiW 12 / TiO 2 the SiW 11 M / TiO 2 (M = Mn, Co, Cu, Ni) its photodegradation research . The experimental results show that the concentration and immersion time of impregnation of the catalyst preparation process , the amount of the catalyst , the initial concentration of the methylene blue solution and the initial pH value is an important factor to affect the dye decoloration rate . Different catalyst degradation under the same conditions and light source decolorization rate . And under the same conditions on the other dyes photocatalytic degradation, the experiments show that the catalyst prepared on the basic dye a better catalytic performance, the maximum decolorization rate reached 95% . Prepared catalyst can be recycled , reused three times , there are still good catalytic performance .
|