| 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 === 100 === In this study, Fe coated TiO2 powders were synthesized using the hydrothermal method. The powders were used as catalyst for decomposing chlorobenzene (CB) and tetrachloroethene (PCE) under microwave irradiation. When the reaction temperature for chlorobenzene in aqueous solution is kept at 30℃,40 ℃,50 ℃ and 60℃,the degradation rate is 10.31%、15.63%、16.71%、20.43% ,respectively. This is because increase of reaction temperature in aqueous solution will enhance the molecular kinetic energy and the number of collision per unit time; thus, lead to a higher removal rate. In test of constant temperature, the degradation chlorobenzene of activation energy is 14.40 kJ/mole. In other side, when raising the microwave energy can lead the degradation rate of CB increased. In 30 watts and 150 watts, the degradation rate of CB is 20.63% and 58.72%, the activation energy is from 48.8kJ/mole reduced to 9.6kJ/mole. Indicate that the microwave power can be effectively provided to the TiO2. Increasing the microwave energy can make TiO2 generating more hole-electron pairs. In different catalytic mediums under microwave energy, 150 watts, after 300 seconds, the degradation rate of CB is 3.5wt% Fe/TiO2 (58.72%)＞1.4wt% Fe/TiO2(53.29%)＞0.7wt% Fe/TiO2 (51.76%)＞Fe0(46.84%)＞0.35wt% Fe/TiO2(43.55%)＞TiO2(37.67%). As the results, the existence of Fe can prevent hole-electron recombination and increase in the total amounts of hydroxyl radicals. In the constant temperature of 60 ℃ and in 150 watts condition, the degradation rate of PCE is better than CB. Because the degradation energy of the ring-chain pollutants is greater than the straight-chain. Under microwave irradiation, using Fe/TiO2 to decompose chloro-containing organic substances is proven to be an effective technology.
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