以鎳-鉍混合氧化物行甲烷蒸氣重組之研究

A study of steam reforming of methane over Nickel-Bismuth mixed oxides

黃明祥(Ming Siang Huang)

指導教授 ： 黃大仁

國立清華大學/工學院/化學工程學系/碩士(2008年)

摘要

本研究以不同含量之鎳(Nickel)鉍(Bismuth)擔載於GDC (Gadolinia-doped Ceria)作為甲烷蒸氣重組反應(steam reforming of methane, SRM)之觸媒，觸媒以共含浸法及二次含浸法二種不同的方法製備而成，反應溫度則介於700℃至850℃之間。由觸媒之BET表面積測定實驗，發現觸媒的表面積隨著金屬的擔載量增加而下降，且Bi對表面積衰減的影響比Ni大；另外，於不同的製作方法上，共含浸法製備之觸媒表面積比二次含浸觸媒大。而在甲烷蒸氣重組實驗方面，發現觸媒的反應性及CO2選擇性隨著Bi含量的增加而呈現增加的趨勢，另外二次含浸觸媒相較於共含浸觸媒有較好的反應活性。而在溫度方面的影響，發現CO2選擇性隨著溫度提升而下降，然而，以Ni-Bi/GDC做為觸媒於反應溫度850℃下仍可維持在95％左右。

關鍵字

二氧化碳選擇性 ； Bismuth ； GDC

並列摘要

Systems of Gadolinia-doped ceria (GDC) supported nickel and bismuth were prepared as catalysts for a study of steam reforming of methane (SRM) reaction. Catalysts were made by co-impregnation and two-step impregnation methods, the reaction temperature is between 700 ℃ to 850 ℃. These systems were characterized by Brunauer Emmett teller(BET) surface area test and steam reforming reaction of methane. The surface area was found to decrease with a increase of metal loading, bismuth especially, and catalysts were made by co-impregnation method exhibited higher surface area than two-step impregnation method. Adding bismuth to GDC promotes both CO oxidation and methane activities, catalysts were made by two-step impregnation method especially. The CO2 selectivity increases proportion to bismuth contents but decreases proportion to reaction temperature. In this study, the CO2 selectivity maintains about 95% at the high temperature 850℃.

並列關鍵字

CO2 selectivity ； Bismuth ； GDC

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