紫外線/二氧化鈦程序處理氣相二氯甲烷及全氟化物(四氟甲烷、六氟乙烷)之研究

Decomposition of Dichloromethane and PerFluoroCompounds in Air Streams by UV/TiO2 Process

葉明倫(Ming-Lun Yeh)

指導教授 ： 鄭福田

國立臺灣大學/工學院/環境工程學研究所/碩士(2009年)

https://doi.org/10.6342/NTU.2009.03058

摘要

本研究利用連續式長形光反應器進行紫外線/二氧化鈦程序處理氣相二氯甲烷及全氟化物(四氟甲烷、六氟乙烷)。將以含浸法製備之二氧化鈦均勻批覆於石英玻璃板上，探討紫外線光強度、滯留時間、相對濕度及反應物初始濃度對二氯甲烷去除率及礦化率之影響。此外，並評估以紫外線/二氧化鈦程序處理具高暖化潛勢且生命週期極長之全氟化物氣體之可行性。
本實驗進一步利用光沈積法改質光觸媒製備Pt/TiO2，探討添加鉑金屬對於光催化效果的影響。由實驗結果發現，利用Pt/TiO2可有效提升氣相二氯甲烷之去除率及礦化率；而處理四氟甲烷及六氟乙烷，則不論光觸媒改質與否，皆因其化學結構穩定幾乎無去除效果。

關鍵字

二氧化鈦 ； 二氯甲烷 ； 全氟化物 ； 暖化潛勢 ； Pt/TiO2

並列摘要

The heterogeneous photocatalytic degradation of the gas-phase dichloromethane and PerFluoroCompounds (PFCs) was performed by using the UV/TiO2 process in a continuous reactor. The rectangular photoreactor contains a quartz plate coating with TiO2 thin film on it. The effect of UV light intensity, retention time, relative humidity and initial concentration of reactant on the removal and mineralization rates of dichloromethane were investigated in this study. Besides, the system was used to assess the feasibility of decomposing PFCs, the compounds with long lifetime and high global warming potential, by the UV/TiO2 process.
Pt/TiO2 catalyst was prepared by photodeposition to determine the effect of Pt addition on photocatalytic efficiency. According to the analytical results, the removal and mineralization rates of dichloromethane were improved by the addition of Pt on TiO2. Neither TiO2 nor Pt/TiO2 could decompose the PFCs (CF4, C2F6) effectively attributed to their chemical stability.

並列關鍵字

TiO2 ； Dichloromethane ； PerFluoroCompounds (PFCs) ； Global Warming Potential ； Pt/TiO2

參考文獻

傅泀翰，以改質光觸媒處理二氯甲烷之研究，國立成功大學環境工程研究所碩士論文(2004)

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