臺灣博碩士論文加值系統

自從哈伯法於一世紀前發明以來，固氮反應完全改變了世界的樣貌。全球超過90%的人口仰賴哈伯法所生產的氨過活。然而，哈伯法的嚴苛反應條件對於偏遠地區來說著實不可行，且在化石燃料價格上漲的未來，哈伯法的操作成本也會增加。在半導體產業蓬勃發展的臺灣，排放量漸增的廢水已成為人民所關注之焦點。利用光催化產氨及分解廢水或將是上述問題之解方。本研究提議使用雙胞反應器同時達成上述兩目的。本研究衡量了觸媒在雙胞反應器初期條件及末期條件的表現。實驗中測試了鐵相關觸媒產氨的活性以及以商用觸媒為基底的材料降解廢水的效果。觸媒經過X光繞射光譜、可見光吸收光譜、掃描式電子顯微鏡、能量色散X射線譜以及比表面積與孔隙度分析儀鑑定。結果顯示Fe-BiOBr產氨的表現優異。P25 (TiO2) 相關觸媒能有效降解廢水。然而，同一觸媒在雙胞初期及後期條件的表現並不一致。Pd-P25在初期有最突出表現，但P25在後期的表現則最突出。

Since the Haber-Bosch process was invented a century ago, the majority of the global population has relied on Haber-Bosch nitrogen to carry on their lives. The fierce operating conditions is not possible in rural areas, and rising fossil fuel prices may impose higher cost of operation in the future.
Wastewater discharge from booming semiconductor industries in Taiwan has grown into an issue as the production chain grows. Hence, photocatalytic production of ammonia accompanied by wastewater degradation in a twin reactor has been proposed. In this work, the conditions in the initial phase and the final phase of the twin reactor operation have been investigated. Iron-related catalysts have been tested for their capabilities of nitrogen reduction. Modified commercial catalysts were tested for their wastewater degradation capabilities. The catalysts were characterized by XRD, UV-Vis, SEM, EDX, and BET surface area analysis. Results showed that Fe-BiOBr exhibited much improved ammonium production rate, and P25 (TiO2) series catalysts demonstrated impressive oxidative power. However, the tested catalysts did not always perform well in every phase of the simulated twin reactor operation. Fe-BiOBr had higher efficiency when reaction was carried out in pure water instead of solution containing electron mediators. Pd-P25 showed superior degradation power in the early phase while P25 performed the best in the late-phase conditions.

Acknowledgement i
摘要 iii
Abstract iv
Table of Contents v
List of Figures x
List of Tables xiii
Chapter 1 Preface 1
Chapter 2 Introduction 3
2.1 Photocatalysis 3
2.1.1 Principles 3
2.1.2 Applications 4
2.1.3 Limitations 4
2.2 Nitrogen fixation 5
2.2.1 Nitrogen cycle in nature 5
2.2.2 Haber-Bosch process 7
2.2.3 Fertilizers, clean energy and sustainability 8
2.2.4 Photocatalytic nitrogen fixation 9
2.2.5 BiOBr and iron-doped BiOBr photocatalyst for nitrogen fixation 10
2.3 Wastewater Remediation 11
2.3.1 Isopropyl alcohol in semiconductor industry discharge 11
2.3.2 Photocatalytic wastewater remediation 12
2.4 Twin reactor system 12
2.4.1 Z-scheme system 12
2.4.2 Electron mediator 13
2.4.3 Ion-exchange membrane 13
2.4.4 Twin reactor design for nitrogen fixation and wastewater oxidation 14
Chapter 3 Experimental Section 17
3.1 Chemicals and Instruments 17
3.1.1 Chemicals 17
3.1.2 Instruments 18
3.2 Photocatalyst preparation 19
3.2.1 BiOBr photocatalyst series for nitrogen reduction 19
3.2.2 Fe2O3 photocatalyst series for nitrogen reduction and isopropyl alcohol degradation 21
3.2.3 C3N4 photocatalyst series for nitrogen reduction 22
3.2.4 WO3 photocatalyst series for IPA oxidation 23
3.2.5 TiO2 (P25) photocatalyst series for nitrogen reduction and wastewater oxidation 24
3.3 Photocatalyst characterization 25
3.3.1 Ultraviolet-visible spectroscopy (UV-Vis) 25
3.3.2 X-ray diffraction (XRD) 26
3.3.3 Scanning electron microscopy (SEM) 27
3.3.4 BET surface area analysis 28
3.3.5 Energy dispersive X-ray spectroscopy (EDX) 29
3.3.6 X-ray photoelectron spectroscopy (XPS) 29
3.4 Experiment Setup 30
3.4.1 Single-chamber reactor for feasibility exploration 30
3.5 Detection of experiment products 32
3.5.1 Nessler’s reagent 32
3.5.2 Ion chromatography 33
3.5.3 Gas chromatography 33
Chapter 4 Results and Discussions 35
4.1 Catalyst characterization 35
4.1.1 Fe2O3, C3N4, TiO2 series 35
4.1.1.1 XRD 35
4.1.1.2 UV-Vis 37
4.1.1.3 XPS 39
4.1.2 BiOBr series 41
4.1.2.1 XRD 41
4.1.2.2 UV-Vis 42
4.1.2.3 SEM 44
4.1.2.4 EDX 46
4.1.2.5 BET surface area analysis 51
4.1.2.6 XPS 52
4.2 Ammonium quantitative analysis 54
4.2.1 Nessler’s reagent 54
4.2.1.1 Effect of iron ions 54
4.2.1.2 Effect of iodide and iodate 56
4.3 Ammonium production 58
4.3.1 Fe2O3, C3N4, TiO2 series 58
4.3.2 BiOBr series in pure water 59
4.3.2.1 Effect of doping 60
4.3.2.2 Effect of illumination power 63
4.3.2.3 Effect of gas feed 65
4.3.2.4 Long-duration tests 69
4.3.3 BiOBr series with electron mediators 71
4.3.3.1 Effect of mediator type and concentration 71
4.3.3.2 Ammonium production in simulated late-phase conditions 73
4.3.4 Summary 75
4.4 IPA wastewater remediation 77
4.4.1 Comparison of TiO2 and WO3 based catalysts 77
4.4.2 Effect of loaded metal type 79
4.4.3 Effect of loaded metal amount 82
4.4.4 Pd-P25 performance in simulated late-phase conditions in a twin reactor 83
4.4.5 Comparison of performance in early-phase and late-phase conditions 85
4.4.6 Summary 87
4.5 Vision for ammonium production and wastewater remediation in a twin reactor 88
Chapter 5 Conclusions 91
References 93
Autobiography 99

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