應用在甲醇水蒸氣重組之Cu/CeO2和Cu/ZnO觸媒研究

Cu/CeO2 and Cu/ZnO Catalysts for steam reforming of methanol

呂嘉哲(Chia-Che Lu)

指導教授 ： 陳炎輝

大同大學/工程學院/化學工程學系所/碩士(2006年)

摘要

摘要
本研究的目的在製備高性能的銅系觸媒，以應用於甲醇水蒸氣重組反應中。觸媒是以共沉澱法來製備，在300℃下煅燒3小時而得。製備Cu/CeO2和Cu/ZnO兩種不同的觸媒來做比較。利用XRD，ICP，BET，和TPR來進行觸媒的特性分析。甲醇水蒸氣反應是在固定床反應器中進行，以水和甲醇莫耳比值1.2當進料，氦氣當做攜帶氣體。觸媒在進行反應前，先以氫氣還原，以比較不同組成的觸媒對於重組反應有何影響，進而尋找最適的觸媒組成。
實驗的結果顯示，觸媒的還原溫度跟BET surface area 有關，BET surface area 越大，所需要的還原溫度越低。Cu/Ce觸媒最高的MeOH轉化率可達97.5%，由反應結果可以看出，Cu/Ce觸媒的反應效果要比Cu/Zn觸媒來的好，Cu/Zn觸媒最高的MeOH轉化率最高為85.8%。

關鍵字

甲醇水蒸氣重組

並列摘要

ABSTRACT
The aim of this study was to prepare the high-performanced catalysts of copper series, for applying in the methanol-steam reforming reaction. The catalysts were prepared with the co-precipitation method and were obtained by calcinations under 300℃ for 3 hours. Two kinds of catalysts of Cu/CeO2 and Cu/ZnO were prepared for comparison. The analysts of characteristics of catalysts were carried out by means of XRD, ICP, BET and TPR. The methanol-steam reforming reaction was proceeded in fixed-bed reactor, with water and methanol in mole ratio of 1.2 as reactants and helium as the carrier gas; the catalysts were reduced with hydrogen before the reaction was carried out so as to compare the effects of catalysts of different compositions on the reforming reaction and to search further by for the optional catalysts compositions.
The experimental results showed that the reducing temperatures of catalysts of catalysts depended upon BET surface area: the larger the BET surface area, the lower the required reducing temperature. The highest MeOH conversion of Cu/Ce catalysts could reach to 97.5%. From the reaction results, it could be seen that, the reaction effects of Cu/Ce catalysts were better than those of Cu/Zn catalysts and that the highest MeOH conversion of Cu/Zn catalysts was 85.8%.

並列關鍵字

steam reforming of methanol

參考文獻

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