ENVR 169 |
| Removal of organic contaminants from water present at low concentrations (ppm or below) requires the use of tertiary treatment methods for complete removal or high mineralization. Among these treatments, combination of chemicals such as ozone and hydrogen peroxide, presence of catalysts both dissolved or as solids and photoradiation systems with different lamps emitting at different wavelengths have been used with success. Among AOPs, use of iron as catalyst and lamps emitting in the near UV and/or visible light spectrum are very interesting to apply because of the abundance of iron in the aquatic environment and similarity to solar light. Fe(III)/UVA oxidation technology is one of these systems. In this AOP system, the presence of some carboxylic acids such as oxalic and tartaric acids has been shown to be very effective in generating free radicals and, as a consequence, to improve the oxidation rates of pollutants in water. In order to test this AOP system, muconic acid has been chosen as a model compound because of its appearance in water as an intermediate of the oxidation of phenols and because intermediates do not interfere in the spectrophotometric determination of both muconic acid and Fe(III) photoactive species (Fe(OH)2+). Then, in this work the effect of different carboxylic acids (oxalic, tartaric, citric, succinic, malonic acids, etc.) has been studied. Also, the pH effect has been discussed. |
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General Papers
6:00 PM-8:00 PM, Wednesday, August 22, 2007 BCEC -- Exhibit Hall - B2, Poster
Division of Environmental Chemistry |