本研究以擔載氧化鎵之奈米碳管(Ga/CNTs)為模板，並以蒸氣輔助結晶法(steam-assisted crystallization，SAC)合成多級孔的Ga/ZSM-5，並與含浸法製備的Ga/ZSM-5及多級孔Ga/ZSM-5進行比較，探討介孔和不同擔載鎵的方式對甲醇芳香化的影響。結果顯示，以CNTs(或Ga/CNTs)為模板所衍生的介孔構造可降低反應物和產物於微孔內的質傳阻力，進而提升芳香族的產率和延長觸媒的壽期。然而，以Ga/CNTs為模板所合成的Ga/ZSM-5，不僅能生成介孔，亦具有良好的鎵分散性及脫氫活性，其原因為較多的(GaO)+能和布朗斯特酸之間行協同效應(Synergetic effect)進而促進甲醇芳香化，於500 oC下的芳香族產率達73%，遠高於其他方式所合成的ZSM-5的產率。一系列的觸媒物化性鑑定，如XRD、BET、SEM、TEM、NMR、ICP、NH3-TPD、H2-TPR、Pyridine-IR、MeOH-TPSR等，將在本論文中探討。

Hierarchical Ga/ZSM-5 catalysts were synthesized by using a one-pot process of
combined hard-templating and steam-assisted conversion. Compared with Ga-incorporated ZSM-5 made by impregnation and by sequential CNTs templating and impregnation, hierarchical Ga/ZSM-5 had a moderate mesoporosity and possibly a high concentration of (GaO)+-Brønsted acid site. The mesoporosity could reduce the mass transfer resistance of products in the porosity. Moreover, the synergy effect between (GaO)+-Brønsted acid site enhances the aromatization activity.Among prepared catalysts, hierarchical Ga/ZSM-5 was the most effective catalyst in methanol aromatization. The aromatics yield of 72.6% was achieved in MTA at 500 oC. All the prepared catalysts were characterized using various techniques including XRD, nitrogen adsorption–desorption, SEM, TEM, NMR, ICP, NH3-TPD, H2-TPR, Pyridine-IR, MeOH-TPSR, TGA.

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