Summary: | 碩士 === 國立高雄第一科技大學 === 環境與安全衛生工程研究所 === 101 === This study is discussed that a degradation of photoreduced dechlorination. The electron of photosensitizer, stimulated by using energy conservation lower power microwave, which via the mechanism of electron transfer reaction, the Chlorinated organic compounds can be reducted by photochemical reduction mechanism. As a results of the dechlorination of Chlorinated organic compounds. before the mechanism of photosensitized electron transfer reaction. Where photosensitizer (PS), initially at a ground state, is activated to a short-lived excited state (PS*) upon absorption of energy from microwave light. The excited state of the PS* donates an electron to the volatile organohalide (RCl), subsequently leading to dechlorination. The results showed that, on the five photosensitizers evaluated, the degradation rate of Chlorobenzene (CB) is methylene blue (33.92%)>Bromocresol green (30.55%)>methyl violet (28.51%)>methyl orange (27.93%)>Phenolsulfonphthalein (26.47%).In the experiment on Effects of Electron Donor Concentrations of Trimethylamine (TMA), the results showed that degradation rate of CB is 3 mM (52.88%)>2 mM (50.70 %)>1 mM (46.27%)>0.5 mM (42.16%) In the experiment on Effects of photosensitizers Concentrations of methylene blue, When the concentration of 0.5 mM was the most effective. As the results, In the performance of best operating conditions of dechlorination reduction , 0.5 mM methylene blue and 2 mM Trimethylamine in 150 watts condition, the degradation rate of PCE is better than CB. Under microwave irradiation, using photosensitizer to decompose chloro-containing organic substances is proven to be an effective technology.
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