由本實驗的研究結果發現，利用銅觸媒催化甲烷的二氧化碳重組反應的過程受到許多反應條件所控制，例如：反應溫度、銅的前驅物、添加物以及擔體的種類等等。在此研究中我們發現銅觸媒表面的積碳現象不但不會使觸媒的催化能力快速衰退，反而可以穩定觸媒的催化活性。由程溫氧化的實驗結果發現銅觸媒表面上的積碳型態至少有三種，分別標示為Cα，Cβ和 Cγ。同時，我們也提出一套在甲烷的二氧化碳重組反應過程中，發生在銅觸媒表面積碳的反應機制。在添加物效應的方面，我們測試了不同種類的添加物對銅觸媒之催化活性的影響。我們發現以任何比例的Cu/Ni/SiO2雙金屬觸媒進行催化甲烷的二氧化碳重組反應，不但可以展現出相當高的一氧化碳生成活性，而且觸媒的穩定度也比單金屬觸媒高出許多。最後，我們希望經由有系統性的實驗設計與結果能做為未來設計出更好的新觸媒之基礎。

The reforming of CH4 reaction with CO2 was studied over supported catalysts. From this study, we have recognized that the catalytic behavior of the copper catalysts were affected by many factors such as the reaction temperature, the categories of precursors of active metals, the additives, and the supports of the catalysts. In this study, it was found that the catalysts having carbon depositions not only performed higher activities but also became more stable. TPO results have shown that three types of carbonaceous species, Cα, Cβ and Cγ, were found to exist on the supported copper catalyst during CH4-CO2 reforming reaction. The mechanism of the carbon deposition was also investigated, and we propose a model to explain this process. The effects of various additives on the performance of the catalysts were also explored. We found that the Cu/Ni/SiO2 bimetallic catalysts exhibited high activities regardless of the ratio of Cu/Ni. These catalysts exhibited higher activity and stability than the monometallic catalyst at 800℃. The deactivation rates of these catalysts were only about 0.15- 0.31% h-1 (after more than 20 hours on stream). Therefore, the Cu/Ni/SiO2 bimetallic catalysts are preferable for the carbon dioxide reforming of methane.

TABLE OF CONTENTS

Chapter One Introduction
1.1 A review of CO2 reforming of CH4
1.2 Research focuses of CO2 reforming of CH4 in the future
1.3 Research Motives

Chapter Two Experimental
2.1 Preparation and characterization of copper catalyst
(1) Preparation and pretreatment of copper catalyst
(2) Temperature-programmed reduction (TPR)
(3) X-ray diffraction (XRD)
(4) Scanning electron microscope - Energy dispersive X-ray spectrometer (SEM-EDS)
(5) Inductively coupled plasma - Mass spectrometer (ICP-MS)

2.2 Measurements of catalytic activities based on various
reaction conditions

Chapter Three Measurements of catalytic activities
3.1 Effect of support on copper catalysts used in the
reforming reaction
3.2 Effect of copper precursor on the behavior of copper catalysts
3.3 Effect of re-treatment on the behavior of copper catalyst
3.4 Effect of reaction temperature on the catalytic activity

Chapter Four Additive effect on the supported copper catalysts

Chapter Five Characterization of carbonaceous species formed during reforming reaction over the supported copper catalysts

Chapter Six Conclusions

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