Photocatalytic Degradation of 2,4,6-Trinitrotoluene in Wastewater Using a Thin-Film TiO2 Reactor

  • Shin, Gi-Bum ;
  • Kim, Yeong-Kwan
  • Published : 2008.03.28


The photocatalytic treatment of water contaminated with 2,4,6-trinitrotoluene (TNT) was explored in bench-scale experiments in batch mode using a Pyrex tube coated with a thin film of $TiO_2$ located inside a photoreactor. The reactor was aerated by purging it with compressed air before initiating the photocatalytic reaction. The rate of TNT degradation approximated first-order kinetics. The reaction rate constant decreased as the TNT concentration increased from 25 to 100 mg/L, while the first-order kinetics could be modeled using a Langmuir adsorption isotherm. The addition of the organic reductants methanol and EDTA significantly enhanced the rate of TNT degradation, with optimum results in the presence of 20% methanol by volume. EDTA increased the rate of TNT removal by enhancing the role of the reductants./ࠀ堡ﺖ⨀愁덀态Ȁ큑⎡ĀāḀ褗덐ᢗヨ⨀塶ヨ⨀覆ヨ⨀?̀適잖⨀똂̀適잖⨀ꁙ똂


TNT;$TiO_2$ thin-film;Photoreactor;Degradation;Adsorption;Kinetics


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