吳乃立臺灣大學：化學工程學研究所張志毅CHang, Chih-YiChih-YiCHang2007-11-262018-06-282007-11-262018-06-282007http://ntur.lib.ntu.edu.tw//handle/246246/52266旋轉反應器 (RDR) 在光觸媒降解之應用近年來受到極高的重視，其不僅可避免懸浮型光觸媒反應器需在操作後需分離光觸媒粉體的問題，並藉由旋轉盤旋轉，使有機污染物可高度均勻混合並產生極薄的液膜，因此光穿透率可顯著提升而大幅極高光反應速率，避免塗佈型光觸媒反應器的常見之質傳限制問題，甚至效能可超越懸浮型光觸媒反應器。 本研究主要分成三部分。首先，將結合旋轉盤流體力學與動力學模式，利用甲基橙在紫外光下之降解速率觀察旋轉反應器之製程特性。實驗結果顯示，在僅有1.6秒之轉盤滯留時間下，甲基澄之光降解轉化率高達55%。此外，藉由轉盤旋轉，不僅可同時增加光反應速率及質傳速率，並能使整體光降解反應速率位於光反應限制區，不受質傳限制之影響。第二，本研究進一步提出旋轉反應器對有機染料的光降解機制，與質傳之機制進行比較，並成功使用軟體模擬轉盤上濃度之變化。結果顯示，模擬之反應機制進一步證明在轉速提升之後能避免質傳的影響。最後，本研究提出旋轉反應器在製程放大的便利性與可能性，其可藉由轉盤之放大而大幅提升光降解之轉化率。Rotating-disk-reactor (RDR) has been received much attention in photocatalysis, which not only avoids the difficult separated process between TiO2 and solution, but would be expected to possess better performance even than the suspension photocatalytic reactors. Three main objectives of this work are to be noted. Firstly, we investigated the process characteristics of RDR on degrading methyl orange (MO) by combining the kinetics model and fluid dynamics model we proposed. The results show that the conversion of MO was up to 55% within 1.6s of retention time. With disk rotating: (1) The photocatalytic reaction rate was greatly improved by light penetration only through the micro-scale liquid film. (2) The mass transfer rate was increased significantly and the reaction is shifted to the photocatalytic reaction rate limitation region. Secondly, the intrinsic mechanism of photocatalytic reaction have been presented and simulated. Last but not least, the possibility of scale-up is discussed in our research. Based on our model, the optimal condition of photocatalytic process could be simply attained by calibrating several parameters, including flow rate, rotating speed, disk size and light intensity.摘要 I Abstract II Table of Contents III List of Figures VI List of Tables X Chapter 1 Introduction 1 1-1 Background 1 1-2 Motivations and Objectives 1 Chapter 2 Literature Review 4 2-1 Introduction of Titanium Oxide, TiO2 4 2-1-1 Fundamental Properties 4 2-1-2 Principles of Photocatalysis 10 2-1-3 Mechanisms for Photocatalysis 14 2-1-4 Applications of TiO2 on Photocatalysis 17 2-2 Introduction of Photocatalytic Reactors 20 2-2-1 Classification of Photocatalytic Reactors 20 2-2-2 TiO2 Slurry Photocatalytic Reactors 21 2-2-3 Immobilized TiO2 Photocatalytic Reactors 22 2-2-4 Configuration of Photocatalytic Reactors 26 2-2-5 Rotating-Disk-Reactor 36 2-3 Introduction of Advanced Oxidation Process 39 2-3-1 Cavitation 40 2-3-2 Fenton Chemistry 41 2-3-3 H2O2/UV, O3/UV, and H2O2/O3/UV Procedures 43 2-3-4 Photocatalytic Oxidation 45 Chapter 3 Experimental 49 3-1 Chemical Reagents and Experimental Instruments 49 3-1-1 Chemical Reagents 49 3-1-2 Experimental Instruments 50 3-2 Rotating Disc Reactor 51 3-2-1 Schema 51 3-2-2 Preparation of TiO2-Coated Discs 53 3-2-3 Fundamental Experiments 55 3-2-4 Comparison with Batch Reactor 56 3-3 Analysis and Characterization 58 3-3-1 Microstructure Characterization 58 3-3-2 Kinetics Analyses 59 Chapter 4 Results and Discussion 62 4-1 Characterization of TiO2-Coated Disk 62 4-2 Characterization of Rotating-Disk-Reactor 65 4-2-1 Flow Pattern 65 4-2-2 Amount of TiO2 Coated on the Disk 65 4-2-3 Temperature Effect 66 4-3 Free Film Model of Rotating-Disk-Reactor 71 4-3-1 Reviews of Free Film Model of Rotating Disk 71 4-3-2 Liquid Film Thickness 72 4-3-3 Average Residence Time 79 4-3-4 Flow Regime of Rotating-Disk-Reactor 81 4-3-5 Kinetics Model of Rotating-Disk-Reactor 83 4-4 Investigation of Mechanisms on Rotating-Disk-Reactor 86 4-4-1 Explanation of Experimental Results 86 4-4-2 Model of Photocatalytic Reaction Limitations 92 4-4-3 Model of Mass Transfer Limitations 95 4-4-4 Initial Concentration of Methyl Orange 96 4-4-5 Comparison of the Experimental Value with Simulation Data 99 4-5 Discussion of Commercial Potential of Rotating-Disk Reactor 105 4-5-1 Comparison of Rotating-Disk-Reactor with Batch Reactor 105 4-5-2 Evaluation of Disc Size for Rotating-Disk-Reactor 106 4-5-3 Scale-up of Rotating Disc Reactor for Commercialization 107 Chapter 5 Conclusion 112 Reference 114 Appendix A 1333842043 bytesapplication/pdfen-US二氧化鈦旋轉反應器甲基橙光降解反應高級氧化程序TiO2Rotating-disk-reactorMethyl orangePhotocatalysisAdcanced Oxidation Processthesishttp://ntur.lib.ntu.edu.tw/bitstream/246246/52266/1/ntu-96-R94524024-1.pdf