Loading...

Synthesis and Evaluation of Nanostructured Photocatalysts for Organic Pollutants Removal from Wastewater

Ahmadi, Mohammad Matin | 2024

5 Viewed
  1. Type of Document: M.Sc. Thesis
  2. Language: Farsi
  3. Document No: 56889 (06)
  4. University: Sharif University of Technology
  5. Department: Chemical and Petroleum Engineering
  6. Advisor(s): Khorashe, Farhad; Ghotbi, Siroos; Larimi, Afsaneh Sadat; Asgharinezhad, Ali Akbar
  7. Abstract:
  8. In this advanced research, titanium dioxide nanotubes were initially synthesized using the hydrothermal method. Subsequently, they were coated with polyaniline, polyindole, or a combination of both polymers using oxidative polymerization. The application of these composites for the removal of the organic pollutant 4-nitrophenol in wastewater was investigated under visible light irradiation from a 250-watt sodium lamp and in the presence of hydrogen peroxide as an oxidizing agent. To characterize the synthesized photocatalysts, various tests were conducted, including X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), UV-Vis diffuse reflectance spectroscopy (UV-Vis DRS), photoluminescence spectroscopy (PL), nitrogen gas adsorption and desorption (BET), field-emission scanning electron microscopy (FESEM), energy-dispersive X-ray spectroscopy (EDX), and transmission electron microscopy (TEM). Performance tests revealed that the 75%PPTN sample exhibited the best photocatalytic performance, consistently demonstrating optimal results in all characterization tests. The impact of various parameters such as pH, time, photocatalyst amount, initial pollutant concentration, and the amount of oxidizing agent was investigated, with the optimal conditions identified as pH 11, reaction time of 120 minutes, 120 mg of photocatalyst, 10 ppm initial pollutant concentration, and 0.5 ml hydrogen peroxide. Under these conditions, 99.46% of the 4-nitrophenol pollutant was successfully degraded. The results clearly indicate the enhancement of the photocatalytic performance by the addition of conductive polymers, improving the surface of TiO2 nanotubes. Stability tests over five consecutive cycles showed consistently high performance exceeding 90%. Additionally, the impact of the absence of various parameters, including light, photocatalyst, and oxidizing agent, was investigated, revealing a significant reduction in performance in their absence. Furthermore, kinetic studies indicated that the reaction of interest follows pseudo-first-order reaction kinetics
  9. Keywords:
  10. Titanium Dioxide ; Organic Pollutant ; 4-Nitrophenol ; Conductive Polymer ; Photodegradation ; Nanophotocatalyst ; Hydrothermal Method

 Digital Object List

 Bookmark

No TOC