近年來，由於氣候變化劇烈，人們已經意識到當前能源生產過程中會排放大量廢氣和廢物，對環境造成巨大影響。為了在生產能源的同時減少浪費，發展清潔能源成為能源領域的熱門話題。生物質氣化是將生物質在高溫下轉化為沼氣的熱處理。沼氣的成分主要是合成氣，如氫氣和一氧化碳，可有效用作生物燃料發電或合成甲醇或其他化學品的原料。然而，氣化過程中不僅會產生合成氣，還會產生焦油。焦油是由多環芳烴組成的複雜混合物。由於焦油的高粘度和酸性，在氣化溫度下降的同時，會造成管道堵塞或管件腐蝕。因此，在氣化過程中開發催化重整以減少焦油並提高合成氣的產量。在本研究中，催化劑的載體是通過共沉澱法製備的。載體以鈣和鋁兩種金屬氧化物製備而成的層狀金屬氧化物的結構，稱為層狀雙氫氧化物(LDHs)，為類水滑石觸媒的基礎。鈣/鋁混合比的範圍為1.5、2.0、2.5，鍛燒溫度範圍為1037、1137、1237 K。 然後，採用濕浸漬法將鎳和鐵附載到載體上。鎳和鐵的負載量範圍皆是3、5、7 wt. %。在製備的過程發現使用不同沉澱劑及溶劑，影響製備出的載體的表面均勻性及晶體生成的尺寸。此外，我們使用田口法來優化催化劑的合成條件，並獲得在重焦油物質轉化的部分，優化出的製備條件為Ca/Al莫爾比為2.5、鍛燒溫度為1073K、3 wt.%的鐵金屬負載量及7 wt.%的鎳金屬負載量。而在氫氣生產的部分，優化出的製備條件為Ca/Al莫爾比為2.5、鍛燒溫度為1073K、5 wt.%的鐵金屬負載量及7 wt.%的鎳金屬負載量。

Owing to the drastic climate changes in recent years, people are the current energy generation will discharge numerous exhausting gas and wastes, which have an enormous impact on the environment. In order to ameliorate pollution from energy production, the development of clean energy has become an imperative topic in the energy field. Biomass gasification is a thermal treatment for converting biomass into biogas at high temperatures. The primary compositions of the bio-syngas contain hydrogen and carbon monoxide, which can be effectively used as biofuels to generate electricity or as raw materials to synthesize methanol or other chemicals. However, not only syngas but also tar will be produced during gasification. Tar is complex mixtures consisted of polycyclic aromatic hydrocarbons. Due to its high viscosity and acidic properties, tar will cause the pipeline blocked or the fittings to corrode while the gasification temperature drops. Therefore, catalytic reforming is developed to reduce tar and enhance the production of syngas during gasification. The support of the catalyst was prepared by co-precipitation. The support is a structure of layered metal oxides, is called layer double hydroxides (LDHs), prepared from two metal oxides of calcium and aluminum, which belong to hydrotalcite-like catalysts. The Ca (calcium)/Al (aluminum) ratio ranges from 1.5, 2.0, and 2.5, and the calcining temperature ranges from 1037 K, 1137 K, and 1237 K. Then, the nickel and iron are loaded onto the support by the wet impregnation method. The loading ranges of nickel and iron are 3, 5, and 7 wt.%. During the preparation process, it was found that the use of different precipitating agents and solvents affects the surface uniformity of the prepared support and the size of crystal formation. In addition, we employed Taguchi's method to optimize the synthesis conditions of the catalyst. Better quality can be obtained through less experimental cost, and the content of heavy tar substances in the synthesis gas during the gasification process can be minimized. In heavy tar conversion, the optimized preparation conditions are Ca/Al molar ratio: 2.5, calcining temperature: 1073K, 3 wt.% iron metal loading, and 7 wt.% nickel metal loading. In hydrogen production, the optimized preparation conditions are Ca/Al molar ratio: 2.5, calcination temperature: 1073K, 5 wt.% iron metal loading, and 7 wt.% nickel metal loading.

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