半導體業之氟系廢水處理仍以添加鈣鹽，產生氟化鈣(CaF2)為主，處理過程中會產生大量高含水率的污泥。雖然上述傳統處理流程可將氟離子濃度降至法定排放標準(<15 mg/L)，但目前台灣面臨現有的掩埋空間明顯不足，導致污泥廢棄置成本大幅提高，因此亟需思考其他可行的處理方式。
    本研究從資源再利用的角度，以結晶方式，利用不同鋁鹽提供合成無機化合物冰晶石（Na3AlF6）所需的鋁離子，與含氟廢液混合後，希望可有效去除水中氟離子以及達到含氟廢液回收再利用之目的。實驗中藉由瓶杯(Jar-Test)試驗方式，探討溶液中氟離子初始濃度、Al/F及Na/F莫耳比、pH值、溫度、反應時間及陰離子濃度，對氟離子去除效率影響。
    實驗結果顯示，於適當的pH範圍下，固定Al/F莫耳比進行反應可有效合成冰晶石，其氟離子回收效率高達89%。如果鋁離子添加過量，容易導致水中多餘Al3+與OH-產生凝膠狀的氫氧化鋁，影響生成冰晶石純度的問題。鋁離子在水中對其它陰離子吸引順序為F->SO42->>Cl->NO3-，因為不同的鋁鹽解離於溶液中的陰離子不同，導致去除氟離子之效率也不同。
    以實廠氫氟酸廢水進行冰晶石結晶實驗，發現分批次添加鋁鹽可以更有效合成冰晶石及回收廢液中的氟離子，其固體產物經X射線繞射儀分析後，含有冰晶石(Na3AlF6)、錐冰晶石(Na5Al3F14)、氟矽酸鈉(Na2SiF6)。在調整pH值時，須注意溶液內會產生放熱反應，添加液鹼時須緩慢加入，避免產生氫氟酸氣體及氟離子濃度減少等問題。

Changing fluoride solubility in solution with addition of calcium salt to precipitate calcium fluoride solid is the most common practice to treat fluoride wastewater generated from semiconductor industry. As the result, large volume of sludge with high water content was produced. Although the above-mentioned traditional treatment process is capable of lowering fluoride concentration below the regulatory discharge limit of 15 mg/L in Taiwan, alternative treatment process is needed due to substantial increase in sludge-handling cost associated with limited landfill space.
    In this study, various aluminum salts were used as aluminum source for the synthesis of cryolite by crystallization in the hope of removing, recycling, and reusing fluoride from fluoride-containing wastewater. Several process parameters such as initial concentration of fluoride, Al/F and Na/F molar ratios, pH, temperature, reaction time and anionic concentration which might affect fluoride removal efficiency were investigated in Jar-Test experiments.
    The results showed that synthetic cryolite was formed effectively within appropriate Al/F molar ratio and pH ranges and fluoride recovery efficiency of up to 89% could be achieved. Excessive addition of aluminum ions with Al/F ratios of higher than 1/6 leads to formation of gelatinous aluminum hydroxide which will affect the purity of synthetic cryolite. Addition of different aluminum salts achieved different fluoride removal efficiency due to the attraction of aluminum ions with various anions which is in the order of F- > SO42- >> Cl- > NO3-.
    Recovery of fluoride by cryolite crystallization was conducted with wasted hydrofluoric acid obtained from an optoelectronic manufacturer. Aluminum salt added stepwisely was more effective than addition of aluminum salt at once for producing synthetic cryolite and removing fluoride. The precipitates solids contain cryolite (Na3AlF6), chiolite (Na5Al3F14), fluorine sodium silicate (Na2SiF6) confirmed by XRD analysis. Cares should be exercised when adding caustic soda to adjust pH of wasted hydrofluoric acid. Heat will be generated due to exothermic nature of the reaction.

目錄
目錄-I
圖目錄-IV
表目錄-X
第一章、前言-1
1-1 研究緣起和目的-1
第二章、文獻回顧-3
2-1工業含氟廢水的來源-3
2-2目前含氟廢水的處理方法-5
2-2-1化學沉澱法-5
2-2-2吸附法-9
2-2-3 流體化床結晶法-13
2-3 氟化物特性及用途-16
2-4合成冰晶石之藥劑種類及特性-19
2-5 以化學平衡軟體模擬不同條件下合成冰晶石之反應-22
2-5-1 鋁離子、鈉離子對水中生成物種之影響-22
2-5-2 含氟廢水初始濃度的影響-28
2-5-3 溫度的影響-32
第三章、實驗材料與方法-33
3-1 實驗材料與設備-33
3-1-1 實驗藥品-33
3-1-2 實驗藥品製備-34
3-1-3 實驗器材-35
3-2 實驗分析方法-36
3-2-1 鋁(Al3+)及鈉(Na+)的分析方法-36
3-2-2 氟(F-)的分析方法-37
3-2-3 結晶物的分析方法-42
3-3 實驗步驟-45
3-3-1 實驗流程圖-45
3-3-2 初步實驗-47
第四章、結果與討論-48
4-1 物理特性之探討-48
4-1-1 結晶顆粒之SEM、EDX分析-48
4-1-2 結晶顆粒之XRD分析-54
4-2 不同鋁藥劑與Al/F莫耳比對於pH值、水中陰離子、反應時間及溫度之探討-56
4-2-1不同鋁藥劑於不同pH值反應後之沉澱物種型態分析-56
4-2-2 含氟廢水與不同鋁藥劑反應後之F-去除率-59
4-2-3 溶液中陰離子之影響-63
4-2-4 反應時間-66
4-2-5 溫度的影響-69
4-2-6 探討兩段式除氟效率-72
4-3 冰晶石顆粒和氟化鈣污泥優缺點之比較-74
4-4 鋁鹽添加量對實廠含氟廢水之探討-76
4-4-1 探討分批次添加鋁鹽處理實廠低濃度含氟廢水之影響-76
4-4-2 探討分批次添加鋁鹽處理實廠高濃度含氟廢水之影響-79
第五章、討論與建議-89
5-1結論-89
5-2建議-92
參考文獻-93

圖目錄
Figure 1 含氟廢水種類流程示意圖 (經濟部工業局,2005)-4
Figure 2 傳統兩階段程序處理含氟廢水-10
Figure 3 新技術含氟廢水處理程續-11
Figure 4 氫氟酸解離物種分佈圖-17
Figure 5 冰晶石(單斜晶系)之結構圖-18
Figure 6 不同Al：F莫耳比下添加鋁離子產生沉澱物種對pH值之影響分佈圖 (模擬條件：溫度25℃，固定氟離子濃度為0.06M及鈉離子濃度為0.03M，改變添加鋁離子濃度)-23
Figure 7 Al/F莫耳比為1：6下溶解態中的剩餘鋁離子所生成型式對pH值之關係圖 (模擬條件：Al/F莫耳比為1：6，未產生固體物中的溶解態鋁離子佔全部加入鋁離子的百分比)-24
Figure 8 不同Al：F莫耳比下氟離子在不同pH產生冰晶石的分佈圖 (模擬條件：溫度25℃，固定氟離子濃度為0.06M及鈉離子濃度為0.03M，改變添加鋁離子濃度)	-25
Figure 9 Al/F莫耳比為0.8：6下溶解態中的剩餘氟離子所生成型式對pH值之關係圖 (模擬條件：Al/F莫耳比為0.8：6未產生冰晶石中的氟離子佔全部加入氟離子的百分比)-25
Figure 10 水中鈉離子濃度對pH值及合成沉澱物種之影響 (a)﹝Na+﹞= 0.03M、(b)﹝Na+﹞= 0.06M、(c)﹝Na+﹞= 0.1M  (模擬條件：Al/F莫耳比為1：6，氟離子濃度為0.06M及鋁離子濃度為0.01M)-27
Figure 11 不同Al：F莫耳比下添加鋁鹽產生沉澱物種對pH值之分佈趨勢圖 (模擬條件：溫度25℃，固定氟離子濃度為0.2M(3800 mg/L)、0.06M(1140 mg/L)、0.02M(380 mg/L)及鈉離子濃度為0.1M、0.03M、0.01M，分別改變添加鋁離子濃度)-30
Figure 12 不同Al：F莫耳比下氟離子在不同pH產生冰晶石的分佈圖 (模擬條件：(a) 溫度25℃，固定氟離子濃度為0.2M及鈉離子濃度為0.1M，改變添加鋁離子濃度(b) 溫度25℃，固定氟離子濃度為0.06M及鈉離子濃度為0.03M，改變添加鋁離子濃度(c) 溫度25℃，固定氟離子濃度為0.02M及鈉離子濃度為0.01M，改變添加鋁離子濃度)-31
Figure 13 不同pH下溫度對合成冰晶石之影響分佈圖 (模擬條件：Al：F莫耳比為1：6，分別氟離子濃度為0.06M、鋁離子濃度為0.01M及鈉離子濃度為0.03M)	-32
Figure 14 鋁檢量線-36
Figure 15 鈉檢量線-37
Figure 16 探討添加緩衝溶液對水中鋁螯合氟離子之影響關係圖	-39
Figure 17 離子層析儀之氟檢量線-40
Figure 18 離子層析儀之波峰光譜圖-40
Figure 19 實驗流程圖-46
Figure 20 含氟廢水與硫酸鋁產生之結晶物進行XRD分析顆粒表面物種 (a) Al：F = 1 : 1、(b) Al：F = 1：3、(c) Al：F = 1：6、(d) 商業冰晶石 (條件：pH5.5，快混3 min (90 rpm)，慢混20 min (30 rpm)；固定氟離子，濃度為1140 mg/L(相當於60 mM/L)調整鋁濃度)-47
Figure 21 含氟廢水與硫酸鋁產生結晶物進行SEM表面型態之觀察 (a) Al：F = 1：1 (b) Al：F = 1：3 (c) Al：F = 1：6 (d) 商業冰晶石-49
Figure 22 含氟廢水與氯化鋁產生結晶物進行SEM表面型態之觀察 (a) Al：F = 1：1 (b) Al：F = 1：3 (c) Al：F = 1：6 (d) 商業冰晶石-51
Figure 23 含氟廢水與聚氯化鋁(PAC)產生結晶物進行SEM表面型態之觀察 (a) Al：F = 1：1 (b) Al：F = 1：3 (c) Al：F = 1：6 (d) 商業冰晶石	-51
Figure 24 冰晶石結晶與氟化鈣污泥之平均粒徑分析 (實驗條件：Al/F = 1：6，NaF+Al(NO3)3初始pH = 5.3、NaF+Al2(SO4)3初始pH = 5.4、NaF+AlCl3初始pH = 5.05)-53
Figure 25 含氟廢水與氯化鋁產生之結晶物進行XRD分析顆粒表面物種 (a) Al：F = 1 : 1、(b) Al：F = 1：3、(c) Al：F = 1：6、(d) 商業冰晶石 (實驗條件：pH5.5，快混3 min (90 rpm)，慢混20 min (30 rpm)；固定氟離子，濃度為1140 mg/L(相當於60 mM/L)調整鋁濃度)-55
Figure 26 含氟廢水與聚氯化鋁(PAC)產生之結晶物進行XRD分析顆粒表面物種 (a) Al：F = 1 : 1、(b) Al：F = 1：3、(c) Al：F = 1：6、(d) 商業冰晶石 (實驗條件：pH5.5，快混3 min (90 rpm)，慢混20 min (30 rpm)；固定氟離子，濃度為1140 mg/L(相當於60 mM/L)調整鋁濃度)	55
Figure 27 含氟廢水與硫酸鋁以不同pH反應下之沉澱物種與商業冰晶石之比照 (實驗條件：氟離子濃度為1140 mg/L，Al/F莫耳比為1比6，pH = 3、4、5、5.5、6、7、9，快混3分鐘、慢混10分鐘)-57
Figure 28 含氟廢水與氯化鋁以不同pH反應下之沉澱物種與商業冰晶石之比照 (實驗條件：氟離子濃度為1140 mg/L，Al/F莫耳比為1比6，pH = 3、4、5、5.5、6、7、9，快混3分鐘、慢混10分鐘)-57
Figure 29 含氟廢水與硝酸鋁以不同pH反應下之沉澱物種與商業冰晶石之比照 (實驗條件：氟離子濃度為1140 mg/L，Al/F莫耳比為1比6，pH = 3、4、5、5.5、6、7、9，快混3分鐘、慢混10分鐘)-58
Figure 30 製備含氟廢水與硫酸鋁試劑以不同pH下反應後之F-去除效率 (實驗條件：Al/F = 1：6 (氟離子濃度為1140 mg/L)、快混3 min和慢混20 min)-61
Figure 31 製備含氟廢水與氯化鋁試劑以不同pH下反應後之F-去除效率(實驗條件：Al/F = 1：6 (氟離子濃度為1140 mg/L)、快混3 min和慢混20 min)-61
Figure 32 製備含氟廢水與硝酸鋁試劑以不同pH下反應後之F-去除效率 (實驗條件：Al/F = 1：6 (氟離子濃度為1140 mg/L)、快混3 min和慢混20 min)-62
Figure 33 化學平衡軟體模擬total F-濃度對添加陰離子及不同鋁試劑反應後的氟去除率之影響 (模擬條件：氟離子濃度為0.06M、鋁離子濃度為0.01M及鈉離子濃度為0.03M，額外添加之陰離子濃度分別為氯離子濃度為0.03M、硝酸根離子濃度為0.03M、硫酸根離子濃度為0.15M)-62
Figure 34 添加不同濃度硫酸根離子(SO42-)對水中Al3+競爭F-之影響 (實驗條件：採用氯化鋁藥劑使Al/F莫耳比為1：6、pH = 5.1±0.1)-63
Figure 35 添加不同濃度鈉離子(Na+)對氟離子去除效率之影響 (實驗條件：採用氯化鋁藥劑使Al/F莫耳比為1：6、pH = 5±0.1)-65
Figure 36 含氟廢水與硫酸鋁於4 hrs反應時間下溶液中氟離子濃度之變化 (實驗條件：Al/F = 1：6、初始pH = 5.3)-67
Figure 37 含氟廢水與氯化鋁於4 hrs反應時間下溶液中氟離子濃度之變化 (實驗條件：Al/F = 1：6、初始pH = 5.13)-67
Figure 38 含氟廢水與硝酸鋁於4 hrs反應時間下溶液中氟離子濃度之變化 (實驗條件：Al/F = 1：6、初始pH = 5.04)-68
Figure 39 硝酸鋁與含氟廢水以不同溫度對F-、Al3+去除效率之影響 (實驗條件：Al/F = 1：6、慢混30 min、pH5.5)-70
Figure 40 硝酸鋁與含氟廢水以不同溫度合成沉澱物進行XRD分析-71
Figure 41 冰晶石顆粒與氟化鈣污泥進行層沉降壓密沉降實驗之比較 (a) 冰晶石(b) 氟化鈣-75
Figure 42 不同Al/F莫耳比分批次添加鋁鹽(硝酸鋁)對F-去除率之影響 (實驗條件：HF初始濃度3000 mg/L、pH5.5、慢混20 min)-77
Figure 43 不同Al/F莫耳比分批次添加鋁鹽(硝酸鋁)產生沉澱物種進行XRD分析 (實驗條件：HF初始濃度3000 mg/L、pH5.5、慢混20 min) (a) mole ratio of Al/F = 0.25：6 (b) mole ratio of Al/F = 0.5：6 (c) mole ratio of Al/F = 1：6 (d) mole ratio of Al/F = 1.5：6 (e) mole ratio of Al/F = 2：6 (f) commerce cryolite-78
Figure 44 反應後溶液色澤及外觀 (a)氫氧化鋁 (b)冰晶石-78
Figure 45 以結晶方式分批次添加鋁鹽(硝酸鋁)對於沉降效率之影響 (實驗條件：HF濃度為43332 mg/L、mole ratio of Al/F =0.25：6、pH5.5、慢混10 min)-81
Figure 46 傳統混凝添加鈣鹽方式處理HF酸廢水 (實驗條件：初始HF濃度40000 mg/L、pH6.5、反應過程所添加鈣離子藥劑為氯化鈣)-82
Figure 47 不同Al/F莫耳比分批次添加鋁鹽(硝酸鋁)對F-去除率之影響 (實驗條件：初始HF濃度40000 mg/L、pH5.5、慢混10 min)-83
Figure 48 添加十次鋁離子藥劑(硝酸鋁)於含氟廢水溶液中反應後對於污泥沉降效率影響之沉降圖Part1 (實驗條件：HF濃度為40000 mg/L、pH5.5、慢混10 min)-85
Figure 49 添加十次鋁離子藥劑(硝酸鋁)於含氟廢水溶液中反應後對於污泥沉降效率影響之沉降圖Part2 (實驗條件：HF濃度為40000 mg/L、pH5.5、慢混10 min)-86
Figure 50 不同Al/F莫耳比分批次添加鋁鹽(硝酸鋁)產生沉澱物種進行XRD分析 (實驗條件：HF初始濃度40000 mg/L、pH5.5、慢混10 min) (a) 1st dosing: Al/F mole ratio of 0.25：6 (b) 2nd dosing: Al/F mole ratio of 0.25：6 (c) 3rd dosing: Al/F mole ratio of 0.25：6 (d) 4th dosing: Al/F mole ratio of 0.25：6 (e) 5th dosing: Al/F mole ratio of 0.25：6 (f) 6th dosing: Al/F mole ratio of 0.25：6 (g) 7th dosing: Al/F mole ratio of 0.25：6 (h) 8th dosing: Al/F mole ratio of 0.25：6 (i) 9th dosing: Al/F mole ratio of 0.25：6 (j) 10th dosing: Al/F mole ratio of 0.25：6 (k) commercial cryolite-87

表目錄
Table 1 一般半導體製程廢水來源種類及水質成分[16]	4
Table 2 鈣離子與常見陰離子反應物種之溶解度積[13]	8
Table 3 流體化床結晶除氟技術之文獻	15
Table 4 藥品參考價格(出處來自於阿里巴巴)	21
Table 5 稀釋後偵測氟離子濃度的讀值	39
Table 6 離子層析儀之波峰值	41
Table 7 不同鋁試劑與含氟廢水混合反應所產生結晶物進行成分的分析	52
Table 8 冰晶石結晶與氟化鈣污泥之粒徑分佈係數	53
Table 9 硝酸鋁與含氟廢水以不同溫度對F-、Al3+去除效率之影響 (實驗條件：Al/F = 1：6、慢混30 min、pH5.5)	70
Table 10 兩段式處理含氟廢水中氟離子以及F-去除率之探討 (實驗條件：Al/F = 1：6、慢混30min、第一階段pH5.5及第二階段pH8.0)	73
Table 11 以混凝方式產生固體物後F-去除效率之比較 (實驗條件﹝冰晶石﹞：mole ratio of Al/F = 1：6、氟離子濃度為1140 mg/L、控制pH = 5.5、慢混10 mins；實驗條件﹝氟化鈣﹞：mole ratio of Ca/F = 1：2、氟離子濃度為1140 mg/L、控制pH = 7.5 、慢混10 mins)	75
Table 12 不同Al/F莫耳比分批次添加鋁鹽(硝酸鋁)對F-去除率之影響 (實驗條件：HF初始濃度3000 mg/L、pH5.5、慢混20 min)	77
Table 13 以結晶方式分批次添加鋁鹽(硝酸鋁)對F-去除率之影響 (實驗條件：HF濃度為43332 mg/L、mole ratio of Al/F =0.25：6、pH5.5、慢混10 min)	81
Table 14 不同Al/F莫耳比分批次添加鋁鹽(硝酸鋁)對F-去除率之影響 (實驗條件：初始HF濃度40000 mg/L、pH5.5、慢混10 min)	83
Table 15 實廠HF酸廢水與硝酸鋁反應後產生固體物進行X-光能量分散光譜儀(EDX)之分析結果	88

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