利用奈米草酸鹽分解/礦化高科技產業含鹵素有害污染物之研發
| 中文摘要 | 台灣半導體業每年使用全氟化物超過300公噸，對於全球暖化與溫室效可能會直接造成影響。半導體業在乾蝕刻及化學氣相層積反應腔清洗製程中須使用全氟化物氣體，而全氟化物對溫室效應的影響遠高過CO2數千倍，對環境與生態造成莫大的衝擊。此外，四氯乙烯為含鹵素廢有機廢溶劑，為目前工業上廣泛使用的溶劑，並已被證實具有致癌性。因此，本計畫主要目的是利用高活性草酸鹽(Li2C2O4、Na2C2O4及K2C2O4三種)，在723-823 K條件下分解/礦化最常使用之四氯乙烯(C2Cl4)及兩種PFCs (NF3及SF6)，取得最佳反應條件、反應動力及機制，評估產物分佈、具附加價值之硫粉及鹽類(LiF/LiCl、NaF/NaCl及KF/KCl)回收再利用之可行性。另外，亦利用XRD、TEM、FE-SEM/EDS、FTIR、XANES/EXAFS，深入瞭解草酸鹽與C2Cl4/PFCs之界面化學及反應機制，以利後續提升去除含鹵素廢液/PFCs效果。草酸鹽大小約為30-50 nm，且形狀為不規則顆粒狀之結晶性粉末。FTIR圖譜可知SF6在草酸鹽礦化分解過程中，SF6明顯已分解並還原成黃色元素態硫，草酸鹽分解生成CO2。EXAFS參數可說明S之氧化價數主要為0價之元素硫，可見SF6在礦化分解過程，SF6確實已分解並還原成元素態硫，且S原子之配位數為1.15，鍵距為1.98 Å。並模擬測試實廠含鹵素廢液及含PFCs廢氣之分解/礦化去除效率，以取得最佳操作條件、工程放大及經濟效益評估，以便提供後續基本工程設計之參考。另外，本計畫亦收集彙整國內外C2Cl4/PFCs之處理及回收減量技術等相關資料，預期本研發技術之執行成果對於溫室氣體管制法亦具相當程度之貢獻。 | ||
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| 中文關鍵字 | 草酸鹽;全氟化合物;含鹵素污染物;催化分解;礦化;溫室效應氣體 | ||
基本資訊
| 專案計畫編號 | EPA-99-U1U4-04-006 | 經費年度 | 099 | 計畫經費 | 1200 千元 |
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| 專案開始日期 | 2010/05/18 | 專案結束日期 | 2010/12/15 | 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-99-U1U4-04-006(final).pdf | 5MB | 利用奈米草酸鹽分解/礦化高科技產業含鹵素有害污染物之研發--定稿本 |
Development of Decomposition/Mineralization of Halogenated Hazardous Organics from High-Technology I
| 英文摘要 | Recently, perfluoro compounds (PFCs) have been widely used in a variety of industrial, commercial, and consumer applications. In Taiwan, over 300 tons per year (TPY) of PFCs are extensively used for etching silicon wafers or cleaning chambers in chemical vapor deposition processes. These compounds are excellent absorbers of infrared radiation and therefore aggravate global warming. In addition, tetrachloroethylene (C2Cl4) is widely used as a cleaner for photoelectronic industries and also recognized very toxic and carcinogentic. Thus, the main objectives were to mineralize C2Cl4 and PFCs (NF3 and SF6) using oxalates (Li2C2O4, Na2C2O4, and K2C2O4). Morphological observations, crystallinity, fine structures, oxidation states of products (e.g. sulfur) were also investigated with FE-SEM/EDS, XRD, FTIR, EXAFS/XANES techniques. Experimentally, they may also have effective destruction of C2Cl4/PFCs by the rapidly capture of F/Cl atoms with subsequent nucleation/mineralization of salts under 573-673 K in few minutes. The morphologies of oxalates were irregular shape of inorganic powders with the particle sizes of 30-50 nm. The XRD patterns of oxalates samples showed are all crystalline structures. FTIR and EDS data also showed that C2Cl4/PFCs may be mineralized completely by oxalates was decomposed to form salts, carbon, sulfur, and CO2. The main species in solid residues were S8 species having the bond distances of 1.98 Å with the coordination number of 1.15. This result indicates that SF6 may be completely mineralized and converted to elemental sulfur and salts. Moreover, the literature databases of comparision with different abatement technologies were completed. From the experimental results, the optimal operation, conversion, mechanism, basic engineering design of oxalate fluidized-bed mineralizer, and economic estimation of a bench-scale fluidized-bed mineralization reactor was also performed to confirm the decompositive effects of C2Cl4/PFCs. | ||
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| 英文關鍵字 | Oxalate;Perfluorinated Compound;Halogenated Pollutant;Catalytic Decomposition;Mineralization;Greenhouse Effect Gases | ||