Degradation of Methylene Blue Using Sunlight with Fixed and Suspended Ag/TiO2 Photocatalyst

In this work, Ag/TiO₂ photo catalyst was prepared by depositing elemental Ag on the surface of TiO₂ particle surface. Ag was got by reducing ion Ag⁺ in the suspension of TiO₂ with illumination of UV light. When it was used to degrade ethylene blue (MB) using UV light, Ag/TiO₂ gave higher catalytic activity than TiO₂. To examine the influence of existing type of catalyst on photo degradation of organic compounds using sunlight, MB was degraded using solar energy with Ag/TiO₂ fixed and suspended separately. Experimental results indicates that it has not much more advantages to degrade organic compounds with catalyst suspended in solution than fixed on somewhere in reactor under the condition of fixing the treating amount of solution per unit time, although the time needed by suspended catalyst is less than that by fixed catalyst for degrading MB to the same concentration. At first, the recovery processing of catalyst will increase the expense. Secondly, the time needed by fixing type TiO₂ will decrease by increasing the reaction area. So, it is necessary to set much more attention on the designing of sunlight photo catalytic reactor with fixing type catalyst. Key words: photo catalyst, sunlight, fix, suspend.