本研究使用貴重金屬鈀觸媒製備在以二氧化鈰為主體之擔體上，進行苯的完全氧化反應。本次實驗二氧化鈰來源有二 :一為信通公司提供二氧化鈰(CeO2-s)擔體，另一為使用沉澱法製備二氧化鈰(CeO2-P)擔體。擔體改質則使用初濕含浸法及共沉澱法將少量釔引入二氧化鈰擔體結構中，形成Ce1-XYXO2-δ擔體。並以初濕含浸法將鈀負載在觸媒擔體上，實驗發現使用共沉澱法將釔引入二氧化鈰擔體結構中，可有效讓Y3+進入二氧化鈰晶格中，取代原本Ce4+位置，增加二氧化鈰氧空缺，提升二氧化鈰儲氧、釋氧能力，達到觸媒對苯完全氧化反應活性之提升。於Ce0.8Y0.2O2-δ-CP擔體負載0.3wt.% Pd之粉末觸媒，在330 ℃可將苯完全氧化。 另在檸檬酸存在下將觸媒直接製備在陶瓷纖維紙上，實驗結果顯現，此法亦可以成功形成Ce1-XYXO2-δ結構，添加少量釔可有效增加觸媒活性，負載在陶瓷纖維紙上之1.0wt.% Pd/Ce0.8Y0.2O2-δ觸媒在290℃即可達到對苯的完全氧化。在100小時耐久性測試中，負載於陶瓷纖維紙上之觸媒，1.0wt.% Pd/Ce0.8Y0.2O2-δ較1.0wt.% Pd/ CeO2觸媒更可維持其觸媒活性，顯現釔的引入不僅增加觸媒活性，並可有效增加觸媒之熱穩定性。 In this thesis, complete oxidation of benzene was studied over Pd/CeO2 and Pd/Ce1-XYXO2-δ. There are two sources of CeO2, CeO2-s(from Nikki) and CeO2-P(by precipitation method),were used. The samples of Yttrium doped Pd/CeO2 (Pd/Ce1-XYXO2-δ) were prepared by impregnation and co-precipitation of yttrium with CeO2. The palladium was loaded on supports by impregnation method. The catalysts were characterized by XRD, TEM, BET, ICP, ESCA, Raman spectroscopy and H2-TPR. The results indicate that Y3+ were successfully incorporated into fluorite structure of CeO2 by co-precipitation method. The activity of catalyst increased. Complete oxidation of benzene over 0.3wt.% Pd/Ce0.8Y0.2O2-δ powder catalysts occur at 330 ℃. The Pd/Ce1-XYXO2-δ catalysts were also co-precipitated in the presence by citric acid on ceramic fiber paper. The characterization of the catalysts also show the formation of Ce1-XYXO2-δ structure. The activity of catalyst was promoted when the amount of yttrium was increased. The temperature for complete oxidation of benzene occurs at 290℃ over 1.0wt.% Pd/Ce0.8Y0.2O2-δ loaded on ceramic fiber paper. After 100 hours reaction, the activity maintains better over 1.0wt.% Pd/Ce0.8Y0.2O2-δ then 1.0wt.% Pd/CeO2 loaded on ceramic fiber paper. The incorporation of yttrium promotes, the activity and thermal stability of the catalyst.
