奈米鈀觸媒擔載於氧化錳-氧化鈰於甲苯完全氧化反應之應用;The Catalytic Properties of Pd/MnOx－CeO2 on Destruction of Toluene

NCU Institutional Repository > 工學院 > 化學工程與材料工程研究所 > 博碩士論文 > Item 987654321/53688

請使用永久網址來引用或連結此文件: http://ir.lib.ncu.edu.tw/handle/987654321/53688

題名:	奈米鈀觸媒擔載於氧化錳-氧化鈰於甲苯完全氧化反應之應用;The Catalytic Properties of Pd/MnOx－CeO2 on Destruction of Toluene
作者:	楊銘彥;Yung,Ming-Yen
貢獻者:	化學工程與材料工程研究所
關鍵詞:	甲苯;氧化錳-氧化鈰;氧化鈰;氧化錳;鈀;觸媒焚化;CeO2;MnOx;MnOx-CeO2;toluene;Palladium;Catalytic combustion
日期:	2012-06-22
上傳時間:	2012-09-11 18:11:05 (UTC+8)
出版者:	國立中央大學
摘要:	氧化錳-氧化鈰觸媒對揮發性有機廢氣焚化有良好活性，奈米鈀/氧化鈰觸媒對於甲苯完全氧化反應有很高的活性。因此，吾人製備鈀/氧化錳-氧化鈰觸媒以期達到更佳的反應活性。在本研究中，製備一系列不同錳/(錳+鈰)比例的鈀/氧化錳-氧化鈰觸媒。先以共沉澱法及氧化還原沉澱法製備氧化錳-氧化鈰，再以初濕含浸法製備0.5 wt. %之鈀觸媒。觸媒鑑定方面，主要是以X光繞射儀(XRD)，穿透式電子顯微鏡(TEM)，高解析度穿透式電子顯微鏡(HRTEM)，X光電子能譜儀(XPS)與程溫還原系統(TPR)，進行鑑定與分析。並使用甲苯作為本研究觸媒焚化之指標物。反應物甲苯之進料濃度為8.564 g/m3 (2085 ppm)，空間流速為10,000 h-1。TEM與HRTEM圖中顯示鈀的顆粒大小約為3到5奈米，且均勻分布於擔體上，其結果與XRD結果一致。由XPS中可發現在適當的錳/(錳+鈰)比例下，有助於鈀元素態與高價錳的比例增加，同時也增進其反應活性。由氧化還原沉澱法製備之氧化錳-氧化鈰擔體較共沉澱法製備之擔體有更大的體積、孔洞體積、表面積、更高的表面錳含量及錳價態，且有特殊的棒狀型顆粒，故擁有更好的反應活性。從活性測試中，鈀/氧化錳-氧化鈰觸媒之反應活性優於鈀/氧化錳、鈀/氧化鈰混合觸媒，證明鈰與錳之間有好的交互作用。實驗結果顯示鈀/氧化錳-氧化鈰觸媒之反應活性優於單一擔體之觸媒，是因為氧化錳與鈀與氧化鈰間有協同作用使得反應活性佳。對於甲苯完全氧化反應，鈀/氧化錳-氧化鈰觸媒是非常好的。MnOx-CeO2 was reported to be active for VOCs combustion and Pd/CeO2 were reported to be very active to destruct toluene from this lab. Therefore, combination of MnOx-CeO2 and palladium is a potential candidate to achieve a catalyst with high activity. In this study, a series of Pd/MnOx-CeO2 catalysts with various ratios of Mn/(Mn + Ce) were prepared. MnOx-CeO2 supports were prepared by co-precipitation method and redox-precipitation method, Pd was loaded by incipient-wetness impregnation method. The Pd loadings in all samples were fixed at 0.5 wt.%. The catalysts were characterized by powder X-ray diffraction (XRD), transmission electron microscopy (TEM), high resolution transmission electron microscopy (HRTEM), X-ray photoelectron spectroscopy (XPS), and temperature-programmed reduction (TPR). The catalysts were tested for total oxidation of toluene. The feed concentration of toluene was 8.564 g/m3 (2085 ppm), with GHSV= 10,000 h-1. The TEM and HRTEM images showed that Pd particle sizes were 3–5 nm and well-dispersed on the support. This result is consistent with the XRD studies. XPS study indicated that the suitable ratio of Mn/(Mn + Ce) able increased the proportion of metallic palladium, the content of high valance state manganese and the catalytic activity. Redox-precipitation prepared MnOx-CeO2 supports have a larger pore volume, surface area, higher manganese valance state, and higher surface manganese amount compare with MnOx-CeO2 prepared by CP method. Moreover MnOx-CeO2 prepared by RP method had a special tube-like shape, so that Pd/MnOx-CeO2 RP had a higher activity. Pd/MnOx-CeO2 catalyst was better than the physically-mixed Pd/MnOx and Pd/CeO2 catalyst, which indicates that there is a strong interaction between ceria and manganese. In conclusion, Pd/MnOx-CeO2 catalysts were superior to Pd/MnOx and Pd/CeO2 catalysts due to the synergetic effect between Ce and Mn. Pd/MnOx-CeO2 catalysts are very promising for toluene destruction.
顯示於類別:	[化學工程與材料工程研究所] 博碩士論文

文件中的檔案:

檔案	描述	大小	格式	瀏覽次數
index.html		0Kb	HTML	579	檢視/開啟

在NCUIR中所有的資料項目都受到原著作權保護.

社群 sharing

資料載入中.....