電容去離子技術(Capacitive Deionization, CDI)技術是一種低能耗、無二次污染的新興脫鹽技術，藉由在兩端電極施加低電壓從水溶液中移除離子。流動式電極電容去離子技術(Flow-Electrode Capacitive Deionization, FCDI)技術，則是進一步將CDI技術中的固定電極改為流動電極，以獲得更高吸附容量及連續操作等優勢。本研究，首先進行FCDI系統的操作參數最佳化，比較不同FCDI操作模式對去除離子效能之影響，並利用CuHCF嵌入式材料應用於FCDI系統中去除地下水中之氨氮。
本研究去除1 g/L的NaCl溶液實驗中，選用最佳化流動電極流速(16 mL/min)、進流水流速(8 mL/min)、襯墊厚度(0.5 mm)並保持進流水與流動電極電解質濃度相同時，去除效率可達99.9%。提高流動電極電解質濃度可以增加系統導電能力進而促進去除效率。
兩種進流水操作模式比較之研究中，和batch-mode相比，single-pass由於有穩定高濃度離子連續供給，所以具有高處理水量、高平均鹽類脫鹽效率(ASRR)、高吸附容量、高充電效率及更快確認進流水離子平衡狀態等優勢，也不會由於濃度差擴大及系統電阻增加，而導致FCDI系統除鹽能力下降。兩種流動電極操作模式比較時，短流式封閉循環(short-circuited closed-cycle, SCC)與獨立式封閉循環(isolated closed-cycle, ICC)相比，由於可以同時進行電吸附與電極再生，所以擁有高去除效率、高ASRR、不需額外的電極脫附程序、pH穩定等優勢。但ICC模式可以推估流動電極中固液相間的離子分佈情況，且可以組建不對稱FCDI系統等優點。
使用嵌入式材料CuHCF與活性碳(AC)作為電極材料的不對稱FCDI系統，研究應用於移除地下水之氨氮可行性，相較於鉀離子，FCDI系統對於氨氮有著更高的選擇性(選擇係數SNH4+/K+=1.07，於混合Na+和K+離子溶液)。在模擬地下水實驗中，發現高濃度的鈉離子與鉀離子的加入，不僅不會因為競爭吸附而降低系統對氨氮的電吸附作用，反而會因為改善系統導電能力而增加系統對氨氮的去除效率(23.5%)並維持優異的離子選擇性，選擇係數SNH4+-N/K+ 與SNH4+-N/Na+為3.22與10.22。使用嵌入式材料CuHCF作為電極材料的不對稱FCDI系統，應用於地下水中氨氮的去除與回收深具潛力。

Capacitive Deionization (CDI) is an emerging desalination technology with low energy demand and without secondary pollution, which removes ions from solution by applying a low voltage between two electrodes. Flow-Electrode Capacitive Deionization (FCDI) replaces the fixing electrode in CDI with the flow electrode for better electrosorption capacity and continuous operation. In this study, we first optimized operation parameters of FCDI system, and then compared the different operation modes to analyze how different operation modes affect the FCDI system. Finally, employing copper ferricyanide (CuHCF) in the FCDI system to remove ammonia in the synthetic groundwater.
In this study, we chose the best flow rate of flow-electrode (16 mL/min), flow rate of inflow (8 mL/min), spacer thickness (0.5 mm), and same electrolyte concentration in flow electrode as the inflow to remove the 1 g/L NaCl solution. The NaCl removal efficiency can reach 99.9%. In addition, increasing the flow-electrode concentration can improve the ion transport ability of system; therefore, it can enhance the salt removal efficiency.
In the comparison of two inflow operation modes, single-pass mode has higher water treatment capacity, higher average salt removal rate (ASRR), higher electrosorption capacity, higher charging efficiency and easier to find the equilibrium condition of inflow because of stable and continuous supply of high concentration of salts. Single-pass mode can avoid the reduction of removal efficiency caused by electric resistance increasing and concentration gradient increasing.
In the comparison of two flow-electrode operation modes, SCC (short-circuited closed-cycle) mode has advantages of higher removal efficiency and ASRR, stable pH value and without regeneration process due to simultaneously electrosorption and regeneration. While ICC (isolated closed-cycle) mode can evaluate the ion distribution between liquid (flow electrode electrolyte) and solid (electrode materials) phases and can construct the asymmetric FCDI system.
When the asymmetric FCDI system using copper ferricyanide (CuHCF) and activated carbons (ACs) to explore the feasibility of removing ammonia from groundwater, the FCDI system achieved higher selectivity of ammonia to potassium (S NH4+/K+=1.07, in Na+and K+ mixture). When the system was applied to the synthetic groundwater, high concentrations of sodium and potassium in the synthetic groundwater instead of competitive adsorption to lower the electrosorption ability to ammonia, but improve the removal efficiency of ammonia (23.5%) and excellent selectivity (SNH4+-N/K+ and SNH4+-N/Na+ : 3.22 and 10.22) because they make better ion transport ability of system. Therefore, applying intercalation material CuHCF to assemble the asymmetric FCDI system has great potential to treat or recover ammonia in groundwater.

第一章	緒論	1
1.1	研究緣起	1
1.2	研究目的	1
第二章	文獻回顧	3
2.1	海水淡化技術	3
2.1.1	多效蒸餾與多級閃蒸技術	5
2.1.2	逆滲透技術	7
2.1.3	電滲析技術與電容去離子技術	7
2.2	電容去離子(CDI)技術	8
2.2.1	原理	8
2.2.2	發展歷史	10
2.2.3	Ragone plot介紹	12
2.3	流動式電極電容去離子(FCDI)技術	14
2.3.1	原理	14
2.3.2	操作模式介紹	16
2.4	嵌入式化合物	19
2.4.1	鐵氰化銅(CuHCF)	21
2.4.2	鐵氰化銅去除氨氮	23
第三章	材料與方法	26
3.1	實驗架構	26
3.2	實驗藥品與設備	28
3.2.1	實驗藥品	28
3.2.2	實驗設備	29
3.3	電極材料製備	30
3.3.1	活性碳(Activate carbon, AC)製備	30
3.3.2	亞鐵氰化銅(CuHCF)材料合成	30
3.4	流動電極製備	32
3.4.1	活性碳流動電極	32
3.4.2	鐵氰化銅流動電極	32
3.5	實驗分析方法	33
3.5.1	X射線繞射分析	33
3.5.2	掃描式電子顯微鏡分析(SEM)	33
3.5.3	感應耦合電漿發射光譜儀(ICP-OES)	34
3.5.4	紫外-可見光分光光譜儀(UV)	34
3.5.5	循環伏安法(Cyclic Voltammetry, CV)	34
3.6	流動式電極電容去離子技術(Flow-electrode capacity deionization)	36
3.6.1	非對稱式流動電極電容去離子技術(Asymmetric FCDI system)	42
第四章	結果與討論	44
4.1	流動式電極電容去離子技術參數最佳化	44
4.1.1	流動電極流速最佳化	44
4.1.2	進流水流速最佳化	48
4.1.3	Spacer厚度最佳化	52
4.1.4	流動電極電解質濃度最佳化	57
4.1.5	參數最佳化總結	61
4.2	流動式電極電容去離子操作模式比較與探討	62
4.2.1	活性碳電化學特性分析	62
4.2.2	單離子Single-pass與Batch-mode比較	66
4.2.3	Na+與K+混合離子Single-pass與Batch-mode比較	76
4.2.4	ICC與SCC比較	84
4.2.5	操作模式綜合比較	92
4.3	CuHCF應用於流動電極電容去離子技術	97
4.3.1	台灣地下水水質情況	97
4.3.2	CuHCF材料特性分析	100
4.3.3	CuHCF材料對單一陽離子的吸附能力	107
4.3.4	CuHCF材料對鉀離子和氨氮混合溶液的選擇性電吸附	113
4.3.5	CuHCF材料對鈉，鉀和氨氮混合溶液的選擇性電吸附	119
4.3.6	CuHCF材料對模擬地下水溶液的吸附能力	126
4.3.7	CuHCF針對氨氮選擇性綜合比較	134
第五章	結論與建議	140

 
List of Figure
Figure 2.1.1 Global desalination technologies share by capacity (AlMarzooqi, Al Ghaferi et al. 2014)	4
Figure 2.1.1.1 Scheme of the standard configuration BR: brine; D: distillate; SW: seawater; HTF: heat transfer fluid (Liponi, Wieland et al. 2020)	6
Figure 2.1.1.2 Multi-stage flash desalination process(El-Dessouky, Ettouney et al. 1999)	6
Figure 2.2.1.1  Scheme of a CDI device	9
Figure 2.2.2.1 Timeline displaying the years when various CDI cell architectures emerged and the corresponding seminal work (Tang, Liang et al. 2019)	11
Figure 2.2.3.1 A conceptual diagram of a CDI Ragone plot(Kim and Yoon 2015)	13
Figure 2.3.1.1 (a) Structure and components of the FCDI cell;(b) Schematic diagram of the FCDI cell in the short-circuited closed-cycle mode (Zhang, Tang et al. 2020)	15
Figure 2.3.2.1 Operational modes of the (a) ICC/batch-mode, (b) ICC/single-pass  (c) SCC/batch-mode, (d) SCC/single-pass and (e) OC/single-pass for FCDI system with regard to flow of feed water and electrodes (Luo, Niu et al. 2020)	18
Figure 2.4.1 (a)Schematics of CDI process based on ion intercalation storage and (b)working mechanism of ion intercalation storage(Liu, Shang et al. 2021)	20
Figure 2.4.1.1  Framework of CuHCF(Wessells, Huggins et al. 2011)	22
Figure 2.4.1.2 Schematic diagram of the FCDI system contained a desalination cell and a concentration cell. CuHCF acted as the cathode of the desalination cell and anode of concentration cell, while AC acted on the contrary (Chang, Duan et al. 2019)	22
Figure 2.4.2.1 Water Ammonia nitrogen quality of Taiwanese river	25
Figure 2.4.2.2  Preference of CuHCF for NH4+ over Na+ and K+(Parajuli, Noguchi et al. 2016)	25
Figure 3.1.1Schematic experimental structure for FCDI system	27
Figure 3.3.1 Copper hexacyanoferrate (CuHCF) preparation procedure	31
Figure 3.6.1 (a)The components of FCDI system, (b) Digital image of FCDI system, (c) Digital image of FCDI system	37
Figure 3.6.2 The Schematic experimental structure of FCDI ICC/Batch-mode system	38
Figure 3.6.3 The Schematic experimental structure of FCDI SCC/Batch-mode system	38
Figure 3.6.4 The Schematic experimental structure of FCDI ICC/Single-pass system	39
Figure 3.6.5 The Schematic experimental structure of FCDI SCC/Single-pass system	39
Figure 3.6.1.1 The Schematic experimental structure of FCDI Asymmetry system	43
Figure 4.1.1.1 (a) Temporal variation of removal efficiency and (b) removal efficiency at different flow rate ratio. Flow electrode flow rate varied from 8, 12, 16, 20 and 24 mL/min. Experiments were performed in SCC/Batch-mode with 2 mm Spacer at a constant voltage of 1.2 V and flow rate of inflow water was fixed at 4 mL/min.	46
Figure 4.1.1.2 (a) Average salt removal rate (ASRR) and (b) adsorption capacity at different flow rates of flow electrode. Flow electrode flow rate varied from 8, 12, 16, 20 and 24 mL/min. Experiments were performed in SCC/Batch-mode with 2 mm spacer at a constant voltage of 1.2 V and flow rate of inflow water was fixed at 4 mL/min.	47
Figure 4.1.2.1 (a)　Temporal variation of removal efficiency and (b)　removal efficiency for the FCDI system at different flow rates of feed water. Feed water flow rates varied from 2, 4, 8 and 16 mL/min. Experiments were performed in SCC/Batch-mode FCDI with 2 mm spacer at a constant voltage of 1.2 V and flow rate of flow electrode was fixed at 16 mL/min.	50
Figure 4.1.2.2 (a)　Average salt removal rate (ASRR) and (b) adsorption capacity for the FCDI system at different flow rates of feed water. Feed water flow rates varied from 2, 4, 8 and 16 mL/min. Experiments were performed in SCC/Batch-mode FCDI with 2 mm spacer at a constant voltage of 1.2 V and flow rate of flow electrode was fixed at 16 mL/min.	51
Figure 4.1.3.1 (a) Temporal variation of removal efficiency and (b) removal efficiency based on hourly observations for the FCDI system at different spacer thickness (0.5, 1, 2 mm). Experiments were performed in SCC/Batch-mode FCDI at a constant voltage of 1.2 V. Flow rate of inflow water and flow electrode were fixed at 8 mL/min 16 mL/min, respectively.	54
Figure 4.1.3.2 (a) Average salt removal rate (ASRR) and (b) adsorption capacity for the FCDI system at different spacer thickness (0.5, 1 , 2 mm). Experiments were performed in SCC/Batch-mode FCDI at a constant voltage of 1.2 V. Flow rate of inflow water and flow electrode were fixed at 8 mL/min 16 mL/min, respectively.	55
Figure 4.1.3.3  Schematic view of the electrical double layer　(EDL) and the diffusion boundary layer　(DBL) formed adjacent to a cation exchange membrane when immersed in an electrolyte solution with a current (Zhang, Ma et al. 2016).	56
Figure 4.1.4.1 (a) Temporal variation of removal efficiency and (b) temporal variation of current for the FCDI system at different NaCl concentrations (1, 5, 10, and 35 g/L). Experiments were performed in SCC/Batch-mode FCDI at a constant voltage of 1.2 V. Flow rate of inflow water and flow electrode were fixed at 8 mL/min and 16 mL/min, respectively. Flow-electrode electrolyte concentration is the same level as inflow concentration.	59
Figure 4.1.4.2 (a) Electric Resistance at 30 minutes and (b) Ragone plot for the FCDI system at different NaCl concentrations (1, 5, 10, and 35 g/L). Experiments were performed in SCC/Batch-mode FCDI at a constant voltage of 1.2 V. Flow rate of inflow water and flow electrode were fixed at 8 mL/min and 16 mL/min, respectively. Flow-electrode electrolyte concentration is the same level as inflow concentration.	60
Figure 4.2.1.1 (a) Cyclic voltammograms of the activated carbon electrode in 1 M NaCl; (b) Specific capacitance (F/g) at different scan rates of the activated carbon electrode in 1 M NaCl	64
Figure 4.2.1.2 (a) Cyclic voltammograms of the activated carbon electrode in 1 M KCl; (b) Specific capacitance (F/g) at different scan rates of the activated carbon electrode in 1 M KCl	65
Figure 4.2.2.1 Temporal variation of Na+ concentration in the NaCl solution for the FCDI system using (a) SCC/batch-mode and (b) SCC/single-pass. Experiments were performed at a constant voltage of 1.2 V. Flow rate of inflow water and flow electrode were fixed at 8 mL/min and 16 mL/min, respectively. Flow-electrode electrolyte concentration is the same as inflow solution at 10 g/L NaCl.	68
Figure 4.2.2.2 Temporal variation of (a) Na+ removal efficiency in inflow, (b) Na+ concentration in flow electrode, (c) pH and (d) current in the NaCl solution for the FCDI system using SCC/Batch-mode and SCC/single-pass. Experiments were performed at a constant voltage of 1.2 V. Flow rate of inflow water and flow electrode were fixed at 8 mL/min and 16 mL/min, respectively. Flow-electrode electrolyte concentration is the same as inflow solution at 10 g/L NaCl.	69
Figure 4.2.2.3 Temporal variation of K+ concentration in the KCl solution for the FCDI system using (a) SCC/batch-mode and (b) SCC/single-pass. Experiments were performed at a constant voltage of 1.2 V. Flow rate of inflow water and flow electrode were fixed at 8 mL/min and 16 mL/min, respectively. Flow-electrode electrolyte concentration is the same as inflow solution at 10 g/L NaCl.	73
Figure 4.2.2.4 Temporal variation of (a) K+ removal efficiency in inflow, (b) K+ concentration in flow electrode, (c) pH and (d) current in the KCl solution for the FCDI system using SCC/batch-mode and SCC/single-pass. Experiments were performed at a constant voltage of 1.2 V. Flow rate of inflow water and flow electrode were fixed at 8 mL/min and 16 mL/min, respectively. Flow-electrode electrolyte concentration is the same as inflow solution at 10 g/L NaCl.	74
Figure 4.2.3.1 Temporal variation of (a) Na+ concentration and (b) K+ concentration in the 10 g/L Na+ and K+ mixture for the FCDI system using SCC/batch-mode. Experiments were performed at a constant voltage of 1.2 V. Flow rate of inflow water and flow electrode were fixed at 8 mL/min and 16 mL/min, respectively. Flow-electrode electrolyte concentration is 10 g/L NaCl.	78
Figure 4.2.3.2 Temporal variation of (a) Na+ concentration and (b) K+ concentration in the 10 g/L Na+ and K+ mixture for the FCDI system using SCC/single-pass. Experiments were performed at a constant voltage of 1.2 V. Flow rate of inflow water and flow electrode were fixed at 8 mL/min and 16 mL/min, respectively. Flow-electrode electrolyte concentration is 10 g/L NaCl.	79
Figure 4.2.3.3 Temporal variation of Na+ and K+ removal efficiency (%) in the inflow of 10 g/L Na+ and K+ mixture for the FCDI system using (a) SCC/batch-mode and (b) SCC/single-pass. Experiments were performed at a constant voltage of 1.2 V. Flow rate of inflow water and flow electrode were fixed at 8 mL/min and 16 mL/min, respectively. Flow-electrode electrolyte concentration is 10 g/L NaCl.	80
Figure 4.2.3.4 Temporal variation of (a) Na+ concentration and (b) K+ concentration in the flow electrode of 10 g/L Na+ and K+ mixture for the FCDI system using SCC/batch-mode and SCC/single-pass. Experiments were performed at a constant voltage of 1.2 V. Flow rate of inflow water and flow electrode were fixed at 8 mL/min and 16 mL/min, respectively. Flow-electrode electrolyte concentration is 10 g/L NaCl.	81
Figure 4.2.3.5 Temporal variation of (a) pH and (b) current in the 10 g/L Na+ and K+ mixture for the FCDI system using SCC/batch-mode and SCC/single-pass. Experiments were performed at a constant voltage of 1.2 V. Flow rate of inflow water and flow electrode were fixed at 8 mL/min and 16 mL/min, respectively. Flow-electrode electrolyte concentration is 10 g/L NaCl.	82
Figure 4.2.4.1 Temporal variation of Na+ concentration in the NaCl solution for the FCDI system using (a) SCC/batch-mode and (b) ICC/batch-mode. Experiments were performed at a constant voltage of 1.2 V. Flow rate of inflow water and flow electrode were fixed at 8 mL/min and 16 mL/min, respectively. Both of flow-electrode electrolyte concentration is 10 g/L NaCl.	87
Figure 4.2.4.2 Temporal variation of total Na+ reduction in inflow and total Na+ increment in flow electrode in the Na+ solution for the FCDI system using (a) SCC/batch-mode and (b) ICC/batch-mode. Experiments were performed at a constant voltage of 1.2 V. Flow rate of inflow water and flow electrode were fixed at 8 mL/min and 16 mL/min, respectively. Both of flow-electrode electrolyte concentration is 10 g/L NaCl.	88
Figure 4.2.4.3 Temporal variation of (a) inflow’s removal efficiency, (b)pH and (c)Current in the Na+ solution for the FCDI system using SCC/Batch-mode and ICC/Batch-mode. Experiments were performed at a constant voltage of 1.2 V. Flow rate of inflow water and flow electrode were fixed at 8 mL/min and 16 mL/min, respectively. Both of flow-electrode electrolyte concentration is 10 g/L NaCl.	89
Figure 4.2.4.4 Ragone plot in the NaCl solution for the FCDI system using SCC/Batch-mode and ICC/Batch-mode. Experiments were performed at a constant voltage of 1.2 V. Flow rate of inflow water and flow electrode were fixed at 8 mL/min and 16 mL/min, respectively. Both of flow-electrode electrolyte concentration is 10 g/L NaCl.	91
Figure 4.2.5 ASRR, charge efficiency, and energy consumption for FCDI using (a)SCC/Batch-mode and (b)SCC/Single-pass under different solution	96
Figure 4.3.2.1 XRD patterns of CuHCF	101
Figure 4.3.2.2 SEM and EDS image of CuHCF at different magnifications	102
Figure 4.3.2.3 Cyclic voltammograms of CuHCF in 1 M (a) NaCl or (b) KCl	104
Figure 4.3.2.4 (a) Cyclic voltammograms of CuHCF in 1 M NH4Cl;(b) Cyclic voltammograms of CuHCF in 1 M NaCl, KCl or NH4Cl at scan rate of 1 mV/s, potential range 0.2 to 1.0 V	105
Figure 4.3.2.5 Specific capacitance (F/g) at different scan rates of the CuHCF electrode in 1 M NaCl, 1 M KCl or 1 M NH4Cl	106
Figure 4.3.3.1 Temporal variation of (a) NH4+-N concentration, (b) total NH4+-N amount changed and (c) pH values in the cathode or anode flow electrode chamber in the 50 mg/L NH4+-N solution for the FCDI system with ICC/single-pass. Experiments were performed at a constant voltage of 1.2 V. Flow rate of inflow water and flow electrode were fixed at 8 mL/min and 16 mL/min, respectively. Both of flow-electrode electrolytes are DI water without adding salts.	109
Figure 4.3.3.2 Temporal variation of (a) K+ concentration, (b) total K+ amount changed and (c) pH values in the cathode or anode flow electrode chamber in the 139.4 mg/L K+ solution for the FCDI system with ICC/single-pass. Experiments were performed at a constant voltage of 1.2 V. Flow rate of inflow water and flow electrode were fixed at 8 mL/min and 16 mL/min, respectively. Both of flow-electrode electrolytes are DI water without adding salts.	110
Figure 4.3.3.3 Temporal variation of (a) removal efficiency in inflow, (b) NH4+ or K+ concentration in the flow electrode electrolyte, (c) pH changes in the cathode flow electrode chamber and (d) current in the 50 mg/L NH4+-N or 139.4 mg/L K+ solution for the FCDI system with ICC/single-pass. Experiments were performed at a constant voltage of 1.2 V. Flow rate of inflow water and flow electrode were fixed at 8 mL/min and 16 mL/min, respectively. Both of flow-electrode electrolytes are DI water without adding salts.	111
Figure 4.3.3.4 Amount changed in the NH4+-N or K+ solution for the FCDI system with ICC/Single-pass. Experiments were performed at a constant voltage of 1.2 V. Flow rates of inflow water and flow electrode were fixed at 8 mL/min and 16 mL/min, respectively. Both of flow-electrode electrolytes are DI water without adding salts.	112
Figure 4.3.4.1 Temporal variation of (a) NH4+-N concentration and (b) Total NH4+-N amount changed in the 25 mg/L NH4+-N and 69.7 mg/L K+ mixture for the FCDI system with ICC/Single-pass. Experiments were performed at a constant voltage of 1.2 V. Flow rates of inflow water and flow electrode were fixed at 8 mL/min and 16 mL/min, respectively. Both of flow-electrode electrolytes are DI water without adding salts.	115
Figure 4.3.4.2 Temporal variation of (a) K+ concentration and (b)Total K+ amount changed in the 25 mg/L NH4+-N and 69.7 mg/L K+ mixture for the FCDI system with ICC/Single-pass. Experiments were performed at a constant voltage of 1.2 V. Flow rates of inflow water and flow electrode were fixed at 8 mL/min and 16 mL/min, respectively. Both of flow-electrode electrolytes are DI water without adding salts.	116
Figure 4.3.4.3 Temporal variation of (a) removal efficiency in inflow, (b) concentration in flow electrode chamber, (c) pH changes in cathode and anode flow electrode chamber and (d) current in the 25 mg/L NH4+-N and 69.7 mg/L K+ mixture for the FCDI system with ICC/Single-pass. Experiments were performed at a constant voltage of 1.2 V. Flow rates of inflow water and flow electrode were fixed at 8 mL/min and 16 mL/min, respectively. Both of flow-electrode electrolytes are DI water without adding salts.	117
Figure 4.3.4.4 Amount changed in the 25 mg/L NH4+-N and 69.7 mg/L K+ mixture for the FCDI system with ICC/single-pass. Experiments were performed at a constant voltage of 1.2 V. Flow rates of inflow water and flow electrode were fixed at 8 mL/min and 16 mL/min, respectively. Both of flow-electrode electrolytes are DI water without adding salts..	118
Figure 4.3.5.1 Temporal variation of (a) NH4+-N concentration and (b) total NH4+-N amount changed in the 100 mg/L NH4+-N, 279.3 mg/L K+ and 164.2 mg/L Na+ mixture solution for the FCDI system using ICC/single-pass. Experiments were performed at a constant voltage of 1.2 V. Flow rates of inflow water and flow electrode were fixed at 8 mL/min and 16 mL/min, respectively. Both of flow-electrode electrolytes are DI water without adding salts.	121
Figure 4.3.5.2 Temporal variation of (a) K+ concentration and (b) total K+ amount changed in the 100 mg/L NH4+-N, 279.3 mg/L K+ and 164.2 mg/L Na+ mixture solution for the FCDI system using ICC/single-pass. Experiments were performed at a constant voltage of 1.2 V. Flow rates of inflow water and flow electrode were fixed at 8 mL/min and 16 mL/min, respectively. Both of flow-electrode electrolytes are DI water without adding salts.	122
Figure 4.3.5.3 Temporal variation of Na+ concentration in the 100 mg/L NH4+-N, 279.3 mg/L K+ and 164.2 mg/L Na+ mixture solution for the FCDI system using ICC/Single-pass. Experiments were performed at a constant voltage of 1.2 V. Flow rates of inflow water and flow electrode were fixed at 8 mL/min and 16 mL/min, respectively. Both of flow-electrode electrolytes are DI water without adding salts.	123
Figure 4.3.5.4 Temporal variation of (a) removal efficiency of three cations in inflow, (b) concentrations of three cations in flow-electrode, (c) pH changes in the cathode and anode chamber and (d) current change in the 100 mg/L NH4+-N, 279.3 mg/L K+ and 164.2 mg/L Na+ mixture solution for the FCDI system using ICC/single-pass. Experiments were performed at a constant voltage of 1.2 V. Flow rates of inflow water and flow electrode were fixed at 8 mL/min and 16 mL/min, respectively. Both of flow-electrode electrolytes are DI water without adding salts.	124
Figure 4.3.5.5 Amount change in the NH4+-N, K+ and Na+ mixture solution for the FCDI system using ICC/Single-pass. Experiments were performed at a constant voltage of 1.2 V. Flow rates of inflow water and flow electrode were fixed at 8 mL/min and 16 mL/min, respectively. Both of flow-electrode electrolytes are DI water without adding salts.	125
Figure 4.3.6.1 Temporal variation of (a) NH4+-N concentration and (b) total NH4+-N amount changed in the 50 mg/L NH4+-N, 250 mg/L K+ and 2000 mg/L Na+ synthetic groundwater for the FCDI system using ICC/single-pass. Experiments were performed at a constant voltage of 1.2 V. Flow rates of inflow water and flow electrode were fixed at 8 mL/min and 16 mL/min, respectively. Both of flow-electrode electrolytes are DI water without adding salts.	129
Figure 4.3.6.2 Temporal variation of (a) K+ concentration and (b) total K+ amount changed in the 50 mg/L NH4+-N, 250 mg/L K+ and 2000 mg/L Na+ synthetic  groundwater for the FCDI system using ICC/single-pass. Experiments were performed at a constant voltage of 1.2 V. Flow rates of inflow water and flow electrode were fixed at 8 mL/min and 16 mL/min, respectively. Both of flow-electrode electrolytes are DI water without adding salts.	130
Figure 4.3.6.3 Temporal variation of (a) Na+ concentration and (b) total Na+ amount changed in the 50 mg/L NH4+-N, 250 mg/L K+ and 2000 mg/L Na+ synthetic groundwater for the FCDI system using ICC/Single-pass. Experiments were performed at a constant voltage of 1.2 V. Flow rates of inflow water and flow electrode were fixed at 8 mL/min and 16 mL/min, respectively. Both of flow-electrode electrolytes are DI water without adding salts.	131
Figure 4.3.6.4 Temporal variation of (a) removal efficiency of three cations in inflow, (b) concentrations of three cations in flow-electrode, (c) pH changes in the cathode and anode chamber and (d) current change in the 50 mg/L NH4+-N, 250 mg/L K+ and 2000 mg/L Na+ synthetic groundwater for the FCDI system using ICC/single-pass. Experiments were performed at a constant voltage of 1.2 V. Flow rates of inflow water and flow electrode were fixed at 8 mL/min and 16 mL/min, respectively. Both of flow-electrode electrolytes are DI water without adding salts.	132
Figure 4.3.6.5 Amount change in the simulated groundwater for the FCDI system using ICC/Single-pass. Experiments were performed at a constant voltage of 1.2 V. Flow rates of inflow water and flow electrode were fixed at 8 mL/min and 16 mL/min, respectively. Both of flow-electrode electrolytes are DI water without adding salts.	133
Figure 4.3.7.1 ASRR, charge efficiency, and energy consumption for FCDI using CuHCF under (a) different water compositions and (b) same molar concentration of ammonia, potassium and sodium.	138
Figure 4.3.7.2 ASRR, charge efficiency, and energy consumption for FCDI using CuHCF under simulated underground water	139
 
List of Table
Table 3.2.1.1 Manufacturers and purity of experimental medicines	28
Table 3.2.2.1 Manufacturers and model of equipment	29
Table 3.4.1 Compositions of Flow-electrodes	32
Table 3.6.1 Experimental solution concentration	42
Table 4.2.1.1 Specific capacitance at different scan rate of the activated carbon in 1 M NaCl	64
Table 4.2.1.2 Specific capacitance at different scan rate of the activated carbon in 1 M KCl	65
Table 4.2.2.1 Multi-parameters comparison in the NaCl solution for the FCDI system using SCC/Batch or SCC/single-pass mode.	70
Table 4.2.2.2 Multi-parameters comparison in the KCl solution for the FCDI system using SCC/batch and SCC/single-pass mode.	75
Table 4.2.3.1 Multi-parameters comparison in the 10 g/L Na+ and K+ mixture for the FCDI system using SCC/batch and SCC/single-pass mode.	83
Table 4.2.4.1 Multi-parameter comparison in the Na+ solution for the FCDI system using SCC/Batch-mode and ICC/Batch-mode	90
Table 4.2.5.1 Total comparison for the FCDI system using different operation mode (1/2)	94
Table 4.2.5.1 Total comparison for the FCDI system using different operation mode (2/2)	95
Table 4.3.1.1 Concentrations of ammonia-nitrogen, sodium, and potassium from different basins or areas in groundwaters in Taiwan	99
Table 4.3.2.1 Specific capacitance at different scan rate of the CuHCF electrode in 1 M NaCl, 1 M KCl or 1 M NH4Cl	106
Table 4.3.3.1 Multi-parameters comparison in the NH4+-N or K+ solution for the FCDI system with ICC/single-pass mode.	112
Table 4.3.4.1 Multi-parameters comparison in the NH4+-N and K+ mixture solution for the FCDI system with ICC/single-pass mode.	118
Table 4.3.5.1 Multi-parameters comparison in the NH4+-N, K+ and Na+ mixture solution for the FCDI system using ICC/single-pass mode.	125
Table 4.3.6.1 Multi-parameters comparison in the synthetic groundwater for the FCDI system using ICC/single-pass mode.	133
Table 4.3.7.1 Total comparison of cation for the FCDI system using CuHCF(1/2)	136
Table 4.3.7.1 Total comparison of cation for the FCDI system using CuHCF(2/2)	137

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