| 摘要: | 二氧化碳作為導致全球暖化的主要原因之一，影響世界各地陸續地出現許多極端氣候並對人民的生活造成嚴重影響。為了解決此問題，除了工廠大幅改善製程減少二氧化碳排放外，利用二氧化碳生產具有高經濟價值的產品或新材料，將是一種更有效和更有前途的方法。在本次的研究中，我們將採用二氧化碳與乙烷進行反應，並藉由乾重組與氧化脫氫反應生成乙烯與合成氣(氫氣和一氧化碳)。
在合成觸媒的階段，我們利用一步到位的蒸汽誘導自組裝法來合成觸媒，藉由結合多種前軀體分子，合成了具有二維六方結構的有序介孔材料。此方式合成的觸媒將會具有表面積大和熱穩定性高等等有助於提升反應的材料特性，並且能使負載金屬可以高度分佈在具有強金屬-載體相互作用的有序介孔通道中，有效地延緩了金屬顆粒的遷移和聚集。我們將利用X光繞射儀（XRD）、穿透式電子顯微鏡（TEM）和氮氣吸附-脫附實驗等方式對觸媒進行材料鑑定，以此來確定是否成功的合成出我們預期的介孔功能材料。
本次實驗選用的負載金屬為鐵跟鎳，因為Ni對整體的反應具有較高的活性，而Fe則具有優秀的氧化還原性能，兩者價格比起貴金屬成本相對便宜且在工業上的使用較不會有限制。在活性測試中，可以得知負載鎳較多的觸媒會促進乾重組反應，產生較多的合成氣，而從負載鐵較多的觸媒得知金屬鐵會促進氧化脫氫反應，促使更多乙烯的生成。因此藉由調整鐵跟鎳的比例以及調整溫度的大小，就能在一定程度上控制產物生成的比例。
綜上所述，本研究運用蒸汽誘導自組裝技術開發出具有特定結構的介孔材料，作為催化二氧化碳再利用反應之觸媒擁有非常良好的材料性質及催化活性，並針對負載金屬的比例進行實驗，了解鐵跟鎳金屬各自對乾重組與氧化脫氫反應的影響，這些實驗結果將幫助我們更加了解觸媒對反應的影響，從而優化觸媒對反應的效果。
;As one of the main contributors to global warming, carbon dioxide is affecting many people due to extreme weather conditions around the world. To address this problem, in addition to significantly improving factory processes to reduce CO2 emissions, using CO2 to produce high-value products or materials is a more effective and promising approach. In this study, we will use carbon dioxide to react with ethane and produce ethylene and synthesis gas (hydrogen and carbon monoxide) through dry reforming and oxidative dehydrogenation reactions.
In the catalyst synthesis stage, we used a one-step evaporation-induced self-assembly (EISA) method to synthesize an ordered mesoporous catalyst with a two-dimensional hexagonal structure by combining various precursor molecules. Catalysts synthesized this way possess material characteristics that contribute to their catalytic performance, such as high thermal stability and large surface area. Additionally, the catalysts allow for the metal to be evenly distributed in ordered mesoporous channels with strong metal-support interactions, which effectively controls the migration and aggregation of metal nanoparticles. Material characterization of the catalysts will be performed using various methods such as X-ray diffraction spectroscopy (XRD), transmission electron microscopy (TEM), thermogravimetric analysis (TGA), and nitrogen adsorption-desorption experiments to determine whether the desired mesoporous functional materials have been successfully synthesized.
For this experiment, we have chosen to load the metals Fe and Ni onto Al2O3 because Ni has a high activity for the overall reaction, and Fe has excellent oxidation reduction performance. Both metals are relatively inexpensive compared to precious metals and suitable for industrial use. In the activity test, we found that the catalyst loaded with more Ni promotes the dry reforming reaction and produces more syngas, while the catalyst loaded with more Fe promotes the oxidative dehydrogenation reaction and leads to more ethylene production. Thus, by adjusting the iron-to-nickel ratio and controlling the temperature, we can regulate the proportion of products to some extent.
In summary, this study utilizes evaporation-induced self-assembly technology to develop mesoporous materials with specific structures. These materials exhibit excellent material properties and catalytic activity as catalysts for carbon dioxide recycling reactions. Additionally, experiments were conducted on the proportion of loaded metals to understand the effects of iron and nickel on dry reforming and oxidative dehydrogenation reactions. These experimental results will help us to better understand the impact of catalysts on reactions and optimize their effects. |
