Faculty of Chemistry, University of Tabriz, Tabriz, I.R. IRAN
The photocatalytic decolorization of aqueous solutions Brown NG, a commercial textile dye, was studied using titana Degussa P-25 as a catalyst for the first time. The experiments were carried out in a batch reactor with the use of artificial light sources (UV-C). The effects of various process variables on decolorization performance of the process have been investigated. The photodegradation of Brown NG was enhanced by the addition of proper amounts of hydrogen peroxide, but it was inhibited by ethanol. Inhibiting effect of ethanol showed that hydroxyl radicals play a significant role in the photodegradation of the dye. In addition, the decolorization efficiency increased with decrease in pH, which implies that the pH is a very important parameter in dye adsorption. The efficiency is inversely related to the dye concentration. Results of TOC analysis show that the organic compounds were degraded, too.
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