應用光觸媒於二氧化碳減量及揮發性有機物去除之技術開發
| 中文摘要 | 本研究主要目的為光觸媒反應器開發及光觸媒改質提升反應效率，本研究分別利用環狀光反應器、新開發之陣列式新型光纖反應器及新型陣列式含pt之光觸媒反應器進行UV/光觸媒程序分解揮發性有機氣相污染物。本研究也利用添加白金、銀來進行光觸媒改質，期以降低光觸媒之電子-電洞結合趨勢，進而促進光觸媒之光利用率，探討改質光觸媒在光觸媒催化程序的影響，依據實驗結果顯示添加白金、銀均能有效提升分解效率。在連續式環狀反應器之反應系統的部分，分別針對氣相污染物異丙醇，探討有關UV光強度、反應物濃度、濕度等操作因素對反應物的轉化率及礦化程度之影響情形，實驗結果顯示以UV/TiO2程序在連續式環狀反應器中進行氣相揮發性有機物的光催化分解研究時，處理效率則主要受UV光強度、氣相有機物進料濃度、相對濕度大小等因素的影響。 另外在氣相光還原部份，則針對相對溼度、不同起始濃度、滯留時間及濕度效應等實驗因子，經實驗分析及鑑定結果後確定光還原產物為甲烷，其主要受到紫外線光強度、濕度、滯留時間及反應物起始濃度等影響。此外，本研究嘗發展出一陣列式新型光纖反應器，並以處理氣相丙酮、甲醛、異丙醇為污染物探討陣列式新型光纖反應器之可行性及其光量子產率。分別改變異丙醇、丙酮、丁酮及甲醛的初始濃度(30-180ppmv)，實驗結果顯示在丙酮初始濃度為30 ppmv時去除率可達61％，隨著初始濃度增加至180 ppmv，去除率下降至約31％，丁酮的去除率也是隨著初始濃度增由52％降低至25％，甲醛去除率為82-46%、異丙醇去除率則為67-42%。 實驗結果顯示連續式微分光纖反應器、陣列式新型光纖反應器之量子產率均比環狀反應器高。但是因為拆裝不容易，此外，若發生觸媒毒化現象，需耗費較大的成本更換光纖，因此，利用光纖反應器的設計原理，開發完成新型陣列式含pt之光觸媒反應器，將改質後之光觸媒直接批覆於陰極燈管表面，如此將能增加光強度，更有效的利用光源。相較於其他有機廢氣處理技術而言，陣列式光觸媒反應系統主要之差異為提高紫外光的利用率與光觸媒氧化能力的提升與維持，為了因應未來實廠的汙染物排放濃度，因此將異丙醇之初始濃度提高至550ppmv，其去除率仍然可以保持在67%；此外，在設備體積上，傳統廢氣燃燒或生物氧化程序須進行燃料提供或曝氣溶解，其質傳床高備受限制，體積也較大，而本項設備則具有空間優勢。 | ||
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| 中文關鍵字 | 揮發性有機物,二氧化鈦,二氧化碳 | ||
基本資訊
| 專案計畫編號 | EPA-95-U1U4-0-12 | 經費年度 | 095 | 計畫經費 | 3596.589 千元 |
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| 專案開始日期 | 2006/11/03 | 專案結束日期 | 2007/08/31 | 專案主持人 | 顧洋 |
| 主辦單位 | 永續發展室(停用) | 承辦人 | 執行單位 | 立曄股份有限公司 |
成果下載
| 類型 | 檔名 | 檔案大小 | 說明 |
|---|---|---|---|
| 期末報告 | 95環保科技育成中心計畫期末報告-內文.pdf | 3MB | [期末報告]公開完整版 |
Photocatalytic Process development for VOCs removal and CO2 reduction
| 英文摘要 | Various volatile organic compounds (VOCs) have been emitted from numerous industries process, many of which in common use are toxic and some are considered to be carcinogenic or mutagenic. Recently, a variety of photocatalytic processes have been studied for treating gaseous streams containing VOCs. However, recombination between electron/hole pairs resulted in low quantum yields for most photocatalytic reactions. Various methods were developed to modify the structural and morphological properties of TiO2 catalyst by doping several metals, such as Pt, Ag, and Au to enhance the photocatalytic activity of TiO2 due to the increase of electron transfer rate to the oxidant and enable visible light absorption by providing defect states in the band gap. The gaseous 2-propanol (isopropanol, IPA) which was decomposed by UV/TiO2 process in an annular photoreactor was influenced by UV light intensity, initial gaseous concentration, relative humidity and so on. In the gaseous photoreduction, the experimental parameters were focused on relative humidity, differential initial concentration, retention time and light intensity, etc. Experimental results obtained in this study demonstrated that UV/TiO2¬ photocatalytic process is capable of carrying the reduction of carbon dioxide in gaseous steams. The primary reduction products from the reduction of carbon dioxide were determined to be methane and methanol. The objective of this research was to investigate the reaction behavior of both the photooxidation of gas-phase volatile organic compounds and the reduction of carbon dioxide in the presence of titanium dioxide, and to develop a photoreactor. A new-type optical fiber photoreactor was investigated for treatment of gaseous acetone, formaldehyde and IPA. After changing the initial concentration of acetone, methylethylketone (MEK), formaldehyde and IPA, from 30 ppmv to 180 ppmv, the degradation rate of these pollutants were from 61 % to 31 %, 52 % to 25 %, 82 % to 46 % and 67 % to 42 %, respectively. In this study, experimental results indicate that the deposition of 0.04 wt% Pt on TiO2 film exhibited the highest photocatalytic activity among all the composition investigated.The new photoreactor was introduced as a superior photoreactor to decompose VOCs. Experimental results showed higher apparent quantum yields were obtained compared with the annular reactor. In order to simulate the actual discharge of factory, the array-photocatalytic reactor was developed and the initial concentration of IPA was increased to 550 ppmv. However, the photodegradation of IPA remained at 67 % in an array-photocatalytic reactor. The results indicated that new photoreactor seems to be more energy-efficient than the annular reactor, which suggested an appropriately designed reactor could be a potential alternative in photocatalytic gas-phase organic compounds treatment. | ||
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| 英文關鍵字 | Various,volatile,organic,compounds,Titanium,dioxide,Carbon,dioxide | ||