隨著世界化石燃料日益減少，尋找新的替代能源即變得急迫，糠醛可由生質廢棄物轉化產生，是一種環保且有價值的平台化合物(platform chemical)，因此如何有效的利用糠醛轉化即為一重要的課題。考量經濟成本，本研究以便宜的鎳金屬為基礎催化糠醛加氫氣相反應，比較不同金屬顆粒大小的Ni/SiO2，發現小顆粒的Ni觸媒具有較高的支鏈脫CO活性，呋喃選擇率較高，大顆粒的Ni觸媒則傾向生成醛基氫化產物糠醇，且產物選擇率受反應溫度影響顯著：低反應溫度適合產生糠醇，高反應溫度則適合產生呋喃及其衍生物如THF、丙烯、丁醛及丁醇，然而兩種鎳觸媒反應後皆因積碳而失活，不過，失活後兩觸媒皆能夠產生單一呋喃產物，是一個有趣又有價值的現象。加入少量第二金屬Pd、Pt、Cu、Fe於Ni/SiO2觸媒會稍微改變產物的選擇性，其中添加Pd最能幫助緩解失活現象，且可以提高丙烯選擇率，但也由於觸媒穩定性增加，失活後觸媒無法選擇性生成單一產物。最後，本研究比較鎳擔載於不同載體時的特性，發現酸性載體SiO2-Al2O3會造成觸媒失活程度加劇，而K-Al2O3及B-SiO2能增加觸媒穩定性，其中Ni/B-SiO2具有較好的反應活性，且其生成丙烯的選擇率為本研究所用觸媒中最高的。

Since currently fossil fuel becomes expensive and less plentiful, there is an urgent need for developing a new alternative energy. Among many candidates, to convert biomass materials, such as furfural, for production of valuable platform chemicals is regarded as one of the most promising alternatives to fossil fuels. How to effectively utilize furfural is an important issue.
In this study, a cheap nickel-based catalyst is considered for gas-phase furfural conversion with hydrogen. The results show that the distribution of products is sensitive to the structure of the Ni-based catalyst. A small particle Ni-based catalyst enhances the decarbonylation reaction while a big particle Ni-based catalyst promotes the producing furfuryl alcohol by hydrogenation. Additionally, the product selectivity is especially affected by reaction temperature. At a higher temperature, more furan and its derivatives such as THF, propylene, butanal and butanol, is produced. At a lower temperature, on the contrary, more furfuryl alcohol is produced. However, it is noted that both nickel catalysts would decay after reaction. Interestingly, the deactivation causes the catalysts can achieve high furan selectivity. Adding second metals, such as Pd, Pt, Cu, Fe, on Ni/SiO2 catalyst would change the product selectivity slightly. Among candidate catalysts, NiPd/SiO2 not only inhibits the deactivation, but also enhances the selectivity to propylene. Extensive studies regarding the support effect have been considered. The results show that acidic support SiO2-Al2O3 causes the catalyst deactivation seriously while K-Al2O3 and B-SiO2 can keep the stability of activity. It is noted that B-SiO2 performs better activity than that of K-Al2O3.

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