以氧化鋯凝膠將觸媒黏著在鋁板材上進行甲醇水蒸氣重組之研究

Study on Aluminum Plates Coated with Zirconia-sol and Catalyst Mixture for Methanol Steam-reforming

謝欣歷(Sin-Li Sie)

指導教授 ： 張志雄

大同大學/工程學院/化學工程學系所/碩士(2008年)

摘要

甲醇水蒸汽重組反應為一高吸熱反應，因而需要大量的熱能以維持反應進行，如何有效率將熱量傳遞到觸媒，減少熱量損失便顯著格外重要。為了使熱量能夠快速傳遞到觸媒本身，本研究利用Zirconia-sol溶液將MDC-3觸媒黏著於鋁板上製成平板觸媒，並將平板觸媒置入新設計的方型反應器（長約26 cm，寬約8 cm）進行實驗。在固定操作條件下（水與甲醇之莫耳比（S/C）為1.5，反應溫度維持在250℃時），探討不同觸媒擔載量、不同觸媒形式對甲醇轉化率、CO選擇率和氫產率的影響，並採用Peppley　建立的甲醇水蒸氣重組動力學模式模擬作為參考。由實驗結果得知，本實驗設計的方型反應器與固定床反應器（PBR）相比有較佳導熱效果，可以有效的減少熱量損失，促使反應器內外部溫度差距縮少，並且保有固定床反應器的觸媒擔載量。當增加觸媒擔載量時，其轉化率、選擇率、產率都有漸漸貼近模擬點；改變置入的觸媒形式對方型反應器熱傳並無太大影響，使用MDC-3顆粒觸媒的甲醇轉化率與平板觸媒相似，但CO選擇率越遠高於平板觸媒。

關鍵字

方型反應器 ； 甲醇水蒸氣反應 ； 反應動力式 ； 商業觸媒 ； 熱傳

並列摘要

Steam reforming of methanol reaction is a high endothermic reaction.
It’s very important to overcome practical heat-transfer limitations, and reduce heat losses. To improve the heat transfer characteristics in a reactor with a desired catalyst loading, a rectangular reactor equipped with aluminum plates is designed for methanol steam-reforming and its performance is investigated. The aluminum plates are coated with zirconia-sol and catalyst mixture. The reforming reactions were carried out in a rectangular reactor packed with the different weight of commercial MDC-3 catalysts to study the effects of different weight on the conversion of methanol and the selectivity of CO over CO2¬ at the same operating conditions(the ratio of water over methanol(S/C) is 1.5, the operating temperature equals to 250℃ ). The reactor performance was evaluated with different plate catalyst loadings and compared with compared with that predicted by the trademark kinetic model proposed by Pepply et al. (1999). The experimental results show that heat conduction of the rectangular reactor is effectual, heat transmits and has not hindered, make the internal and external difference in temperature not big, the heat energy that consumes is smaller than the packed-bed reactor. When increase the weight of MDC-3 catalyst, the conversion of methanol, the selectivity of CO over CO2, the yield of hydrogen are fit to simulation point gradually. Because that heat energy transmits to the catalyst directly, the selectivity of CO over CO2 is lower than that using the particle catalyst of MDC-3 simply.

並列關鍵字

Methanol steam reforming ； Rectangular reactor ； Commercial catalyst CuO/ZnO/Al2O3 ； Reaction kinetics ； Heat transfer

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