碩士 / 弘光科技大學 / 環境工程研究所 / 95 / Abstract
Ozone, due its high oxidation and disinfection potential, has recently received much attention in water treatment technology. Despite several advantages of using ozone, it has a few disadvantages, which limit its application in water treatment technology. The main are relatively low solubility and stability in water. Because of both the high cost of ozone production and only partial oxidation of organic compounds present in water, the application of ozonation might not be feasible from an economic point of view. The objective of this study was to evaluate the heterogeneous catalytic ozonation process in mitigating the taste and odor causing compounds - 2-MIB. The surface water samples were collected from eutrophic reservoirs. Furthermore, the synthetic waters that matrix take from ground water and adding appropriate concentration of 2-MIB was also test in this study. The reaction types including batch, semi-batch and continuous flow reaction, respectively. The titanium dioxide (TiO2) was applied for catalyst in this work. Experimentally, it was found that combined use of O3 and TiO2 catalyst leads to a conspicuous 99% of 2-MIB degradation which compares favorably to the 20~30% obtained more than in the absence of the TiO2 catalyst. The electron paramagnetic resonance (EPR) was used to detect ozone-produced paramagnetic radicals. The experimental EPR spectra verified that more hydroxyl radicals (OH．) generated in the TiO2 catalytic ozonation process. In this system, elevated concentrations of OH． radical produced by the reaction of ozone with catalyst at the solid-liquid interface, is the main cause responsible for the improvement of ozonation induced by the presence of catalyst. At the constant dosage of TiO2 in the semi-batch tests, 2-MIB conversion rate can be approach to 85%, especially in the high pH conditions. In the continuous flow reactor which packing Raschig ring matrix (coating TiO2 films on the surface using Arc ion plating method), 2-MIB degradation rates was obvious high than ozone only reaction system. It was also found that the chlorophyll-a content in the O3/TiO2 effluent was lower than ozone only system, indicated that the high reactivity of OH． radicals were generated by O3/TiO2 during the oxidation process that effectively degraded algal cells and 2-MIB.
| Identifer | oai:union.ndltd.org:TW/095HKU05515007 |
| Date | January 2007 |
| Creators | Cheng, Yung-Ling, 曾勇霖 |
| Contributors | Huang, Winn-Jung, 黃文鑑 |
| Source Sets | National Digital Library of Theses and Dissertations in Taiwan |
| Language | zh-TW |
| Detected Language | English |
| Type | 學位論文 ; thesis |
| Format | 126 |
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