DEGRADATION OF METHYL ORANGE BY TIO2/POLYMERIC FILM PHOTOCATALYST

Degradation of methyl orange (MeO), as a model compound, in the presence of immobilized polymeric titanium dioxide (TiO2) catalyst was investigated. Degussa P25 TiO2, Polyvinyl alcohol, and Polyvinylpyrolidone were used to prepare polymeric film immobilized photocatalyst. The photocatalyst pore size varied between 50 and 300 mu m while its pore density ranged from 7 to 10 pores per square mm. Adsorption of MeO over the catalyst film followed the Langmuir adsorption isotherm. The degradation kinetics of MeO followed the well-known Langmuir-Hinshelwood (L-H) type model. The degradation rate increased at higher initial concentrations while flow rate had a negative impact on the degradation rate. pH of the solution influenced the degradation rate, with higher degradation rates observed in acidic solutions. Degradation rate was also increased with increasing light intensity up to a certain level, beyond which it remained almost unchanged. Total organic carbon (TOC) content of MeO was also measured during the degradation process. It was observed that the TOC decreased substantially with time. The degradation efficiency was 85 %.