engleski

TiO2/Chitosan Films ; Photocatalytic Oxidation of Aliphatic Acids

The development of the TiO2/chitosan photocatalytic films will be described within this study. Two different commercial TiO2 powders were integrated within the matrix of chitosan molecules as a thin layer films. Films were characterized by several methods ; Raman, FT-IR, UV-vis spectroscopy and thermogravimetric analysis (TGA). The developed films contain the high amount of the TiO2, which structure appeared to be intact. The efficiency of the photocatalytic oxidation of the selected aliphatic acids (formic and oxalic acid) was studied. Results obtained regarding the TiO2/chitosan films application showed a similarity with the results of the oxidation performed in the slurry batch reactor. Furthermore, a negligible loss in the mass of the film was observed after the 1-hour experiment, pointing at the both TiO2 and chitosan releasing in the solution. An increment in the TOC value was detected in the first 10 minutes of the processes, giving the conclusion of the presence of the chitosan in the solution. In order to determine the rate of chitosan release and the rate of its oxidation during the UV irradiation of the films, a set of blank tests was performed. A kinetic model describing the photocatalytic oxidation of the studied acids was developed on the basis of the Langmuir-Hinshelwood kinetics. A probability factor was included in the model describing the probability of the acid molecule collision with the film surface.

TiO2 photocatalysis; photocatalytic film; aliphatic acid

nije evidentirano