Loading...

Study and Improvement of Nano-photocatalytic Process Fordegradation of Chemical Contaminants

Moradi, Sina | 2013

795 Viewed
  1. Type of Document: M.Sc. Thesis
  2. Language: Farsi
  3. Document No: 44709 (06)
  4. University: Sharif University of Technology
  5. Department: Chemical & Petroleum Engineering
  6. Advisor(s): Rashtchian, Davood; Vosoughi, Manouchehr
  7. Abstract:
  8. In this thesis, photocatalytic oxidation as a potential method for the treatment of organic environmental contaminants is deeply investigated. While the photocatalytic degradation of various organic compounds under UV light irradiation has been widely investigated, visible-light-induced photocatalytic degradation of low-levels of the pollutants such as Dibenzothiophene (DBT) and 2-Nitrophenol (2-NP) are occasionally reported. In the present work, Lanthanide / Polyethylene glycol -modified TiO2 (La/PEG/TiO2) and Fe,Cu,S/TiO2 have been successfully synthesized by a sol–gel method. The photocatalysts were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and UV–vis diffusive reflectance spectroscopy (DRS). Moreover, the photocatalytic degradation of contaminants under visible light irradiation are investigated for the first time using the new synthesized photocatalyst. The effects of important operational parameters such as initial contaminant concentration, catalyst loading, pH and amount of H2O2 on the degradation efficiency were studied. Kinetics parameters of the photocatalytic oxidation of DBT were also calculated. The results show that DBT decomposition occurs according to the Langmuir–Hinshelwood mechanism. The degradation products were analyzed by GC–MS technique.In the second part of the thesis, the activation of TiO2 photocatalyst for photocatalysis under the visible light using dye-sensitized-TiO2 is described. Adjustment of the pH enhanced the photocatalytic activation of TiO2in the presence of visible light. This confirms that the adsorption of a dye on TiO2 surface is an important factor in dye-photosensitization. The dye-sensitized photocatalysis under visible light was applied to the decomposition of 2-Nitrophenol
  9. Keywords:
  10. Visible Light ; Nanophotocatalyst ; Chemical Contaminant ; Titanium Dioxide ; Response Surface Method ; Dibenzothiophene (DBT) ; Dye Sensitization

 Digital Object List

 Bookmark

No TOC