The Prepared Of TiO₂/Beads Photocatalyst And The Research Of The Photocatalytic Degradation Property

In this paper, TiO2/Beads photocatalyst is synthesized by acid catalyzed sol method using beads as the carrier. The morphology, structure and composition of the composites are characterized by SEM, EDS, XRD, FT-IR. The factors which affect photocatalytic degradation of dyes and the degradation product of dyes, are also investigated by the variation of UV-vis spectra, TOC and COD values.(1) TiO2/Beads photocatalyst is prepared, and the influence of calcination temperature and the content of TiO2 on the structure and degradated activity are studied. The prepared photocatalyst maintain the hollow spherical structure of the bead, and the crystal type of TiO2 which coated on the surface of beads is mixture of anatase and rutile. The photocatalytic property is enhanced. While calcinate the precursor at 500℃, the TiO2 content of four times coated photocatalyst is 26.2%, and the photocatalyst exhibit the highest photocatalytic activity.(2) With the morphology analysis, we didn't find the morphology of beads were changed in the prepared process. XRD patterns show the TiO2 crystal type is anatase while calcinate at low temperature, and it change to rutile while the calcinated temperature increased. Finally, the prepared TiO2/Beads photocatalyst is coated with mixed crystal of anatase/rutile. EDS spectra shows the four times coated photocatalyst has the highest TiO2 content, and the result is verified by TiO2 content measuring experiment.(3) With the TiO2/Beads photocatalytic degradation experiment, the methyl orange dye wastewater was decolorized sonly with the proper light source. The FT-IR spectra, COD, TOC, and the final degradation products shows that the dyes absorbed on the photocatalyst surface, and after a series of photocatalytic oxidation reaction, the solution of the azo dyes completely mineralized to CO2 and inorganic ions, such as NO3-,SO42-and NH4+.