工學院: 環境工程學研究所指導教授: 席行正劉冠宏Liu, Kuan-HungKuan-HungLiu2017-03-062018-06-282017-03-062018-06-282016http://ntur.lib.ntu.edu.tw//handle/246246/277277由於汞的高毒性與生物累積性特性，及由NO所衍生的光化學煙霧與PM2.5，燃煤電廠(CFPPs)所排放出的汞(Hg)及NOx已受到全球極大重視。而國內每年產出大量的廢稻殼，也亟待更具附加價值之資源化處理。本研究利用水熱合成法製備廢稻殼資源化中孔隙二氧化矽(SiO2)載體，透過含浸法分別將MnOx與MnOx-CeOx負載於廢稻殼SiO2載體上，並將材料用於同步去除汞以及NOx。SiO2所含浸的氧化金屬改質比例為5及20 wt%的MnOx搭配5及10 wt%的CeOx。研究結果顯示，MnOx及MnOx-CeOx的摻入造成SiO2顆粒比表面積值與孔體積的降低；同時可以觀察到在所有MnOx摻雜SiO2樣品當中，MnOx(5%)-CeOx(5%)/SiO2觸媒具有最大的比表面積值(SBET = 123 m2/g)。由SEM及TEM圖中可以觀察到，經由金屬氧化物改質的二氧化矽為3-10 μm的板狀顆粒物，Mn4+/Mn3+與Ce4+/Ce3+為MnOx-CeOx/SiO2樣品中主要的價態，然而Mn4+/Mn3+的比例會經由CeOx的加入而提高，透過XRD及XPS分析可以確認本研究材料表面存在無定形/高度分散及結晶相的MnOx。 Hg0及NO的同步控制去除是透過MnOx/SiO2與MnOx-CeOx/SiO2介於150至350度的測試煙氣下進行。值得注意的是MnOx-CeOx/SiO2在低溫的環境底下，相對於MnOx/SiO2都顯現出較高的deNOx及deHg潛勢；於寬廣的溫度操作窗口下(100-300°C)，MnOx(20%)-CeOx(10%)/SiO2皆呈現出接近100%的NO還原能力，而且在150°C底下其汞的去除率為96%。此外Langmuir-Hinshelwood模式擬合結果可成功解釋MnOx及MnOx-CeOx改質觸媒對於汞的去除機制，這些結果都顯示出資源化再利用的廢稻殼所產出的MnOx-CeOx/SiO2吸附劑/觸媒對於Hg0/NOx的去除具有高度潛力。Mercury (Hg) and NOx emissions from coal-fired power plants (CFPPs) have both aroused greatest concern globally due to the high toxicity and bioaccumulability of Hg and the formation of photocatalytic smog and secondary PM2.5 from NOx, respectively. A marked amount of waste rice husk produced in Taiwan also needs to be treated or resource-recovered through a more cost-benefit approach. In this study, MnOx and MnOx-CeOx impregnated SiO2 particles were developed from waste rice husk via a hydrothermal synthesis for simultaneous removal of Hg and NOx. MnOx of 5 and 20 wt% associated with 5 and 10 wt% CeOx was impregnated into the resource-recovery mesoporous SiO2. The presence of MnOx and MnOx-CeOx was shown to decrease the BET surface area and pore volume of the SiO2 particles. It was observed that MnOx(5%)-CeOx(5%)/SiO2 catalyst possessed the largest specific surface area (SBET = 123 m2/g) among the MnOx-impregnated samples. SEM and TEM images indicated that the metal oxide-impregnated SiO2 catalysts had plate-shaped particles with sizes of 3-10 μm. Mn4+/Mn3+ and Ce4+/Ce3+ were the major valence states in the MnOx-CeOx/SiO2 samples. However, the ratio of Mn4+/Mn3+ increased after adding CeOx. The presence of both amorphous/highly dispersed and crystalline MnOx was confirmed by the XRD and XPS analyses. Multipollutant control of the Hg0 and NO was achieved by both MnOx/SiO2 and MnOx-CeOx/SiO2 at between 150 and 350°C under the tested gas conditions. Notably, MnOx-CeOx/SiO2 showed greater low-temperature deNOx and deHg potentials than MnOx/SiO2 sample, with MnOx(20%)-CeOx(10%)/SiO2 having nearly 100% reduction of NO under a broad operation window (100-300°C) and removal efficiency of Hg of 96% at 150°C. Langmuir-Hinshelwood model can successfully explain the deHg by MnOx and MnOx-CeOx/SiO2 catalysts. These results indicate that resource recovery of waste rice husk for producing SiO2 adsorbent/catalyst for Hg0/NOx removal is successful.3579608 bytesapplication/pdf論文公開時間: 2019/8/24論文使用權限: 同意有償授權(權利金給回饋學校)汞氮氧化物二氧化矽錳鈰氧化物燃煤電廠MercuryNOxSiO2Mn-Ce oxidescoal-fired power plant[SDGs]SDG11thesis10.6342/NTU201601891http://ntur.lib.ntu.edu.tw/bitstream/246246/277277/1/ntu-105-R03541101-1.pdf