| 摘要: | 本研究開發電漿觸媒技術去除氣流中NOx和N2O，其主軸可分為兩個方向，一是利用電漿系統作為臭氧產生器，臭氧結合觸媒催化氧化NO，一是電漿結合觸媒催化轉化N2O。臭氧結合觸媒催化氧化NO研究結果顯示FeMnCo/Al2O3觸媒和FeMnCe/Al2O3觸媒可以顯著促進NO深度氧化，提升N2O5的生成量，減少O3逃逸。FeMnCo/Al2O3與FeMnCe/Al2O3觸媒能促進NO氧化為N2O5的速率，即使較短的氣體停留時間（1.2 s），也能展現良好的活性，這在實際應用中有利於降低APCD所需的反應器尺寸與成本。當操作溫度等於100℃時，使用FeMnCo/Al2O3觸媒和FeMnCe/Al2O3觸媒時，NO轉化為N2O5的效率分別為81.8%和90.9%。此外，FeMnCe/Al2O3觸媒具有更好的穩定性。本研究利用COMSOL Multiphysics 軟體進行動力學模型模擬，結果顯示與實驗結果趨勢基本一致。SO2和N2O的存在不會影響NO深度氧化，也不與臭氧發生反應氧化。水氣存在會促進NO的深度氧化，最終生成HNO3，但反應緩慢需要較長的氣體停留時間。電漿結合觸媒催化轉化N2O研究結果顯示，隨著操作電壓的增加，N2O轉化率上升。在相同的操作電壓下，隨著N2O濃度或氣體流量的增加，N2O的轉化率降低。當N2O濃度為1,000 ppm，操作電壓為16 kV時，N2O的轉化率可達96.9%。當操作電壓增加至18 kV，N2O的轉化率略微下降至93.9%，主要是因為N2O分解產物N2(1Σ+)和O(3P)會重新生成N2O。氧氣的存在會降低N2O轉化率，當使用觸媒且操作電壓為18 kV時，加入5%氧氣使總氣體流量為500 mL/min的N2O轉化率由86.7%降至50.6%。氧氣的存在還會提高NO和NO2的生成量，而使用FeMnCe/Al2O3觸媒可以減少NO和NO2的生成量。在電漿觸媒催化氧化系統中同時引入NO和N2O，NO會使得N2O轉化效率降低，但NO可以部分被去除。使用單一的電漿觸媒技術較難實現NO和N2O同時去除，需要技術聯合實現NO和N2O的去除。;This study aims to develop plasma catalysis technology to remove NOx and N2O from gas streams. The research can be divided into 2 aspects: (1) catalytic oxidation of NO via combined ozone which is produce by plasma system as ozone generator and catalysis, and (2) catalytic conversion of N2O via combined plasma and catalysis. Experimental results indicate that FeMnCo/Al2O3 and FeMnCe/Al2O3 catalysts can significantly improve the deep oxidation of NO, enhance the generation of N2O5, and reduce the escape of O3. FeMnCo/Al2O3 and FeMnCe/Al2O3 catalysts show good activity even with a shorter residence time (1.2 s), which is beneficial to reduce the size and cost of APCDs in practical application. When the operating temperature was increased to 100°C, the conversion of NO into N2O5 could reach 81.8% and 90.9% over FeMnCo/Al2O3 catalyst and FeMnCe/Al2O3 catalyst, respectively. Furthermore, FeMnCe/Al2O3 catalyst exhibits better stability. The kinetic model simulation results using COMSOL Multiphysics software is almost consistent with the trend of the experimental results. Furthermore, the presence of SO2 and N2O could not affect the deep oxidation of NO and react with ozone. The presence of water promotes the deep oxidation of NO and produces HNO3, but it requires a long gas residence time due to low reaction rate. On the other hand, experimental results indicate that the conversion of N2O increases with increasing of operating voltage. At the same operating voltage, the N2O conversion decreased with the increase of N₂O concentration or total gas flow rate. When the N₂O concentration was 1,000 ppm and the operating voltage was 16 kV, the N₂O conversion reached 96.9%. However, when the operating voltage was increased to 18 kV, the N₂O conversion slightly decreased to 93.9%. This is primarily because the products of N2O conversion (N2(1Σ+) and O(3P)) can reproduce N₂O. The N2O conversion decreased from 86.7% to 50.6% with addition of 5% oxygen with a total gas flow rate of 500 mL/min and an operating voltage of 18 kV. The presence of oxygen also increased the generation of NO and NO2, while the application of FeMnCe/Al2O3 catalyst could reduce it. When NO was introduced into plasma catalysis system, NO could suppress the N2O conversion, but NO could be removed partially. It is more difficult to achieve simultaneous removal of NO and N2O with a single plasma catalysis technology. Therefore, a combination of technologies is required to achieve this. |
