甲烷為導致全球暖化的氣體之一，為減緩全球暖化，將甲烷轉化為高經濟價值的化學品已成為重要的議題。另一方面，如何有效利用大氣中氮氣的方法也尚未被完全探討。乙腈 (Acetonitrile, ACN) 廣泛應用於多種領域如分析、醫藥、紡織等，本實驗室先前之研究發現可使用氮化鎵為觸媒將甲烷轉化為乙腈，但觸媒表面之可移動式氮將在反應中消耗。在此研究中，我們發現擔載碳化鉬 (MoCx) 催化劑可以同時活化甲烷和氮氣形成乙腈，並製備了一系列碳化鉬催化劑以分析物理化學性質，通過XRD和XAS鑑定催化劑的相態，以流通氮氣或氬氣測試甲烷轉化來驗證氮氣被活化並與甲烷反應形成乙腈。反應6小時後產率達到17.28 h-1並出現明顯的失活，推測失活為觸媒表面覆蓋的焦炭引起，為改善此不足，我們在氫氣、甲烷和氮氣共同進料的條件下進行反應，成功得到高穩定性的乙腈產量。根據 XPS以及參考文獻，推斷氫氣可以抑制焦炭的形成。最後，我們通過結合FT-IR光譜、N2-TPD和動力學分析的結果推測反應機制。

In this work, we found that supported molybdenum carbide (MoCx) catalysts can simultaneously activate methane and nitrogen to form acetonitrile (ACN). A series of MoCx catalysts were prepared and their physicochemical properties were analyzed, catalyst phase was confirmed by XRD and XAS, methane conversion was tested in either nitrogen or argon stream to verify that gaseous N2 was activated and reacted with CH4 to form ACN. After testing for 6 hours, the yield reached 17.28 h-1 and an apparent deactivation occurred. It was speculated that this deactivation was caused by coking. To obtain a stable ACN production, the reaction was conducted by co-feeding H2, CH4 and N2, showing a high stability in the production of ACN. Co-feeding H2 was found to be benefit to suppress coke formation. Finally, we revealed the reaction mechanism of CH4 and N2 co-activation by Mo2C catalyst by the combined results of FT-IR spectroscopy, N2-TPD and kinetic analysis.

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