本研究以具氧空缺之鐵鈰混合氧化物觸媒進行二氧化碳脫氧反應，以共沉澱法合成不同鐵鈰比例之觸媒，探討觸媒中氧化鈰與氧化鐵之可能的交互作用力，進行兩部份討論。第一部份研究中，以程溫氫氣還原H2-TPR與程溫二氧化碳脫氧TP-CO2進行反應，測試比例與反應性的關係，結果顯示所有觸媒大約在400 °C開始脫氧反應，並在600 °C結束，含鐵量較高的觸媒有較高的脫氧反應量，指出混合氧化物中，鐵為二氧化碳脫氧反應的主要貢獻者，實驗室前人研究結果得知，若比較鐵含量相同的鐵鈰混合氧化物與鐵擔載在SBA-15上，鐵鈰混合氧化物具有較佳的反應性，顯示CeO2與Fe2O3之間的交互作用力可提高脫氧反應能力。從穩定性測試結果得知，在600 °C恆溫下進行5次H2還原- CO2脫氧後，鐵鈰混合氧化物仍有氧空缺形成及二氧化碳脫氧活性。第二部分利用臨場傅立葉轉換紅外線光譜儀分析在TP-CO2程序中，二氧化碳在氧化物上的吸附及反應，先分析新鮮與經氫氣還原後的CeO2與Fe2O3，觀察到新鮮鐵鈰混合氧化物同時有CO2在純CeO2的Bidentate carbonate吸附與純Fe2O3上的1111 cm-1振動訊號，氫氣還原後的鐵鈰混合氧化物則無看到還原後CeO2的吸附訊號，只有與還原後Fe2O3相似的1117 cm-1振動訊號，推測脫氧反應主要發生在鐵鈰混合氧化物中的鐵。

In this study, cerium and iron mixed oxides are prepared by co-precipitation method and the oxygen vacancies are applied for oxygen stripping of CO2. In order to illustrate the interaction between CeO2 and Fe2O3 in catalyst, we examine the oxides of different Ce/Fe ratio. The reaction activity is examined by a test procedure of sequential H2-TPR and TP-CO2. The results show that the deoxygenation reaction has an onset temperature at about 400 °C with all the catalysts, and with a maximum at around 600 °C under the test conditions. The iron-rich catalysts have a higher CO2 deoxidation capacity. This indicates that iron-phase of the mixed oxides contribute the main CO2 deoxygenation activity. The stability test shows that the mixed oxide can retain oxygen vacancies generation and CO2 deoxygenation reactivity in 5-cycle H2-reduction-CO2-deoxygenation at 700 °C. In-situ FTIR is applied for examining the adsorption and reaction of CO2 species on the oxide surface. Bidentate carbonate is found on both fresh and reduced CeO2. Bidentate carbonate on fresh CeO2 gradually desorbs with increasing temperature while bidentate carbonate on reduced CeO2 remains presence when it reaches 700 °C. The species can probably indicate the presence of surface oxygen vacancy. Thus, there could be some oxygen vacancies on 700 °C reduced CeO2. We detected both the bidentate carbonate from fresh CeO2 adsorption and 1111 cm-1 vibration mode from fresh Fe2O3 on the fresh cerium iron mixed oxide. However, we can only find 1117 cm-1 from reduced Fe2O3 on the reduced cerium iron mixed oxide. It indicates that iron-phase of the mixed oxides mainly participate in the CO2 deoxygenation.

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