Preparation And Degradation Application Of TiO₂ Supported Zeolite Photocatalyst

To promote the mass production of photocatalystic technology, we conducted a study of TiO2 supported on molecular sieves, using the removal rate of chroma as the evaluation index for the degradation efficiency of catalyst. This study is divided into two parts, as follows:?1?First, we prepared supported TiO2 photocatalyst and undertook an evaluation and characterization of its activity. We used in situ producing method in the process, controlled the volume ratio of butyl titanate, distilled water, ethanol, hydrochloric ethanol to 5:1:5:12.5 and used molecular sieve 13 X as carrier. Under a supporting capacity of 67% and calcination temperature of 400 ?, after two hours of calcination, we managed to get supported TiO2 photocatalyst with the highest activity. The distribution of particle diameters showed that the average particle diameter of the catalyst was about 4.8 ?m under the optimum supporting capacity, which is ideal for the separation and recycle. BET results indicated that the specific surface area of molecular sieve is 522.1 m2/g, while molecular sieves with a supporting capacity of 67% have a larger specific surface area of 33.9 m2/g, which provided precondition for its remarkable adsorption performance. XRD spectrum showed that the framework structure of molecular sieves still existed after supporting TiO2, while TiO2 excited on the surface of molecular sieves in the form of anatase. FT-IR spectrum indicated chemical bonds were formed between TiO2 and molecular sieves, binding them together firmly. TEM pictures evidenced that TiO2 existed on molecular sieves in the form of anatase.?2?Secondly, we conducted a test of the degradation efficiency of TiO2 photocatalyst supported on molecular sieves. In the degradation efficiency test which we used active violet X-2R as the main simulating pollutant, the catalyst performed very well. When the initial concentration of the active violet X-2R solution is 30 mg/L, the catalyst dosage is 8 g/L, without manipulating the initial p H value and adding H₂O2, when the degradation reaction lasted for 180 minutes, the chromophoric groups of the active violet X-2R were fully opened and the removal rate of CODCr reach 66.05%. After comprehensive tests of the removal rate of chroma and CODCr using active violet X-2R, methylene blue and rhodamine B as three simulating pollutants, we concluded that TiO2 supported on molecular sieves is qualified as a broad-spectrum catalyst.