以ZIF-67衍生之鈷基碳催化劑摻雜氧化錳奈米粒子應用於二氧化碳/氫氣甲烷化反應

Synthesis of Manganese Oxide Nanoparticles-dope ZIF-67-Derived Co-based Carbon Catalysts for Carbon Dioxide/Hydrogen Methanation Reactions

蘇紹瑜(SHAO-YU SU)

指導教授 ： 林義?

中原大學/工學院/化學工程學系/碩士(2022年)

https://doi.org/10.6840/cycu202201383

摘要

隨著極端氣候的頻繁發生，環保意識逐漸抬頭，人們開始關注碳排放的議題，淨零碳排放已然成為大家的共同目標，而碳排放的大宗以二氧化碳為主，因此若能透過二氧化碳捕捉並再利用的方式，便能在減少二氧化碳的同時，還能生產出具經濟價值的產品，甲烷便常見的產品之一。在淨零碳排放的展望下，能源轉型也是十分重要的，而使用甲烷做為能量儲存介質的電轉氣技術(Power to Gas)，結合了能源轉型議題以及二氧化碳再利用，既減少了碳排放，又改善了可再生能源的間歇性問題，因此二氧化碳甲烷化可望成為能源轉型以及減少碳排放的重要關鍵。
二氧化碳甲烷化需借助催化劑來進行，過去文獻上多以釕、銠及鎳當作催化劑金屬材料，而釕及銠因其高昂的成本而難以普及，鎳也因為對於硫及一氧化碳的耐受性低而存在穩定性問題，且除了催化效能，較低催化的溫度也更有助於提高能源效率。而鈷有著不亞於鎳的活性，對於硫及鎳又有更高的耐受性，更有利於煙道氣等複雜氣體，較低的催化溫度，也創造以廠房廢熱做能量來源的可能。沸石咪唑骨架(ZIFs)是一種良好的氣體捕捉材料，具有高比表面積及獨特的結構，在鍛燒後能透過獨特結構避免金屬團聚現象發生，故以ZIF-67為主體，藉由獨特結構提升鈷的分散度，結合氧化錳奈米粒子的摻雜，形成鈷/氧化錳的介面，該介面與二氧化碳具有較低的結合能，提升了低溫催化的能力。
本研究製備出以ZIF-67衍生之氧化錳奈米粒子摻雜鈷基碳催化劑應用於二氧化碳/氫氣甲烷化反應，經多項材料鑑定確認合成氧化錳摻雜的鈷基碳催化劑，透過調控不同金屬比例、不同溫度及不同氣體流量等參數對於甲烷化反應之影響，以氣相層析儀(Gas Chromatography)分析反應結果，證實氧化錳奈米粒子的摻雜對於低溫下的催化存在正面效果，並透過重複利用及長時間操作驗證其穩定性。

關鍵字

甲烷化反應 ； 氫化反應 ； 二氧化碳再利用 ； 電轉氣 ； 沸石咪唑骨架 ； 氧化錳摻雜鈷碳材

並列摘要

With the frequent occurrence of extreme climates, environmental awareness has gradually risen, and people have begun to pay attention to carbon emissions. Net zero carbon emissions have become a common goal, and carbon dioxide is the main source of carbon emissions. Therefore, if carbon dioxide can be captured and reused, it can be reduced to produce economically valuable products. Methane is one of the most common products. Under the prospect of net zero carbon emissions, energy transition is also very important, and the Power to Gas technology using methane as an energy storage medium combines energy transition issues and carbon dioxide reuse, which not only reduces carbon emissions, it also improves the intermittent problem of renewable energy, so carbon dioxide methanation is expected to become an important key to energy transition and reducing carbon emissions.
Carbon dioxide methanation needs to be carried out with the help of a catalyst. In the literature, ruthenium, rhodium and nickel are mostly used as catalyst metal materials. Ruthenium and rhodium are difficult to popularize due to their high cost, Nickel also has stability problems due to its low tolerance to sulfur and carbon monoxide. In addition to catalytic efficiency, lower catalytic temperatures also contribute to improved energy efficiency. Cobalt has an activity no less than nickel, and has higher tolerance to sulfur and nickel, which is more conducive to complex gases such as flue gas. The lower catalytic temperature also creates the possibility of using the waste heat of the plant as an energy source. Zeolite imidazole frameworks (ZIFs) are good gas capture materials with high specific surface area and unique structure. After calcination, the unique structure can avoid the occurrence of metal agglomeration. Therefore, using ZIF-67 as the precursor, the unique structure improves the dispersion of cobalt, combined with the doping of manganese oxide nanoparticles to form a cobalt/manganese oxide interface, which has a low binding energy with carbon dioxide, which improves the low-temperature catalysis ability.
In this study, a Manganese Oxide Nanoparticles-dope ZIF-67-Derived Co-based Carbon Catalysts is prepare for Carbon Dioxide/Hydrogen Methanation Reactions, and the synthesis of catalyst was confirmed by multiple material identifications. By adjusting the effects of different metal ratios, different temperatures, and different gas flow parameters on the methanation reaction, the reaction results were analyzed by gas chromatography, It is confirmed that the doping of manganese oxide nanoparticles has a positive effect on the catalysis at low temperature, and its stability is verified through long-term operation.

並列關鍵字

methanation reaction ； hydrogenation reaction ； carbon dioxide reuse ； Power to gas ； zeolite imidazole framework ； manganese oxide doped cobalt carbon material

參考文獻

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