表面改質二氧化鈦奈米管應用於環境中有機及硝酸鹽污染物去除技術之研發
| 中文摘要 | 本計畫主要目的乃開發二氧化鈦奈米管(TNs)之合成條件及其特性分析，並深入探討TNs 之結構差異，及對不同特性染料廢水測試光催化及吸附之效能。更將二氧化鈦奈米管負載金屬銀(Ag/TNs)以增進光催化之效果，並將對反應動力及參數取得及其應用於處理酸性染料、硝酸/亞硝酸鹽廢水以及3 種環境荷爾蒙污染物。TNs 光催化對的不同染料的去除率依序為Basic Violet10>Basic Green 5>Methylene Blue>Acid Blue 9 ， 且使用簡化之Langmuir-Hinshelwood 來描述染料的光催化動力模式，其中Basic Violet 10分解速率最佳，K 值約為0.00894 min-1。由FE-SEM 及TEM 結果可知，負載銀之粒徑約為3 ~ 4 nm。由UV/Visible 光譜分析結果可知，Ag/TNs 在450~ 550 nm 之間會有強烈的吸收峰。透過XANES 及EXAFS 光譜探討Ag/TNs之配位數及鍵長，對TNs 之第一層Ti-O 分析，配位數為2，鍵長約1.95 Å；對Ag/TNs 之第一層Ag-O 分析，配位數為1.6，鍵長約2.28 Å。另外，以不同電洞捕捉劑測試於光催化系統中對亞硝酸鹽之去除效率，結果顯示甲酸效果較草酸為佳。以Ag/TNs 處理60 ppm 之硝酸鹽廢水，在30 min 內硝酸鹽廢水的去除率約70%；3 h 內硝酸鹽廢水去除率均可達到100%。故推測以Ag/TNs 處理硝酸鹽廢水的產物以氨氮及氮氣為主。此外，亦完成大面積Ag/TNs 薄膜UV/Vis 催化反應器之基本工程設計及經濟影響評估，以落實利用Ag/TNs 去除環境污染物技術本土化之目標。 | ||
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| 中文關鍵字 | 二氧化鈦奈米管, 光觸媒, 吸附, 光催化, 金屬銀, 水熱法, 染料, 亞硝酸鹽, 硝酸鹽, 環境荷爾蒙污染物, 同步輻射光譜 | ||
基本資訊
| 專案計畫編號 | EPA-97-U1U4-04-004 | 經費年度 | 097 | 計畫經費 | 1325 千元 |
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| 專案開始日期 | 2008/06/05 | 專案結束日期 | 2009/03/31 | 專案主持人 | 林錕松 |
| 主辦單位 | 永續發展室(停用) | 承辦人 | 林燕柔 | 執行單位 | 元智大學 |
成果下載
| 類型 | 檔名 | 檔案大小 | 說明 |
|---|---|---|---|
| 期末報告 | EPA-97-U1U4-04-004(final)-上傳版.pdf | 4MB | [期末報告]公開完整版 |
Technical Development of Surface-modified Titania Nanotube for the Removal of Organics and Nitrate Contaminants from Environment
| 英文摘要 | The main objectives of the present study were to prepare titanium dioxide nanotubes (TNs) in large quantities by hydrothermal routes and to characterize the photocatalytic properties, fine structures, formation mechanisms of TNs, and Ag-loaded TNs for enhancing the removal efficiency of dyes, nitrate, nitrite, and three environmental hormones pollutants in wastewaters. From the experimental data of the dye wastewaters removal under UV light irradiation, the photodegradative efficiencies of four kind of dyes solutions on TNs were basic violet 10>basic green 5>methylene blue>acid blue 9. In addition, a simple Langmuir-Hinshelwood was used and calculated to describe the reactions of the dye wastewaters. Basic Violet 10 photodecomposion rate was the highest photocatalytic efficiency with a K of 0.00894/min. Ag/TNs characterized using FE-SEM and TEM showed that the diameter of silver particle was 3-4 nm. The UV/Vis spectra revealed that the maximum adsorption wavelength of TNs was 450-550 nm. By using XANES spectra, the valency and framework of Ag/TNs were Ti(VI) with anatase-type structure, and Ag-O bonding for Ag/TNs. The EXAFS data also revealed that Ag/TNs have a first shell of Ti-O (Ag-O) bonding with a bond distance of 1.95 (2.28) Å and a coordination number of 2 (1.6). From the experimental data of the nitrite/nitrate removal under UV light irradiation, two kind of hole scavengers showed that the photodegradative efficiency of formic acid was higher than the one of oxilic acid. Experimentally, Ag/TNs reacted with nitrate solutions of 60 mg/L originally. The concentrations of nitrate contaminants in solutions decreased obviously onto Ag/TNs. After the reaction of 30 min, the removal efficiency of nitrates in solutions was 70% and reached 100% after 3 h. It notably appeared that the nitrate species was partly converted to ammonia and nitrogen gases. Finally, the basic enginnering design and cost evaluation for a large-surface aligned Ag/TNs thin film/UV-Vis photocatalytic reactor system were primarily performed in order to enhance the localized decontamination abilities and technologies in Taiwan | ||
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| 英文關鍵字 | Titania nanotube, Photocatalyst, Adsorption, Photocatalysis, Silver nanoparticle, Hydrothermal method, Dye, Nitrite, Nitrate, Environmental hormone, XANES/EXAFS | ||