7-1 結論
本研究成功製備新式可見光式奈米級二氧化鈦/奈米級零價鐵複合材 料，證實可以當作為水處理氧化與還原藥劑，並且可以使用可見光 LED 與 CCFL 激發反應並可有效處理生物難分解之雙偶氮染料，研究中亦證實二氧 化鈦確實可以延緩零價鐵表面氧化物沉積與零價鐵可以防止二氧化鈦電子 再回覆現象。並且可以回收再利用達到綠色材料功能，研究中並以結合反 應 UV/H2O2/NTFC 處理高 TOC 廢水，解決零價鐵無法有效處理 TOC 之困 難，研究中也推論 NTFC 反應機制分為三階段，第一階段吸附與還原反應，
第二階段氧化反應，第三階段吸附 core-shell 反應與自發性電池反應，此研 究結果有助於新式材料之發展與反應機制之了解，主要研究結果綜述如下〆
1. 高表面積與高效能 NTFC 研製
(1) 以低溫 pH 中性之方法合成二氧化鈦並以改良方式製備高表面積與 高效能之零價鐵，並利用化學鍵結方式增強二氧化鈦與零價鐵覆膜。
(2) NTFC 具有可見光激發之特性，可見光 NTFC 可以以約 490 nm 藍光 與綠光 CCFL 與 LED 當激發光源。
(3) NTFC 反應後段會形成奈米材料 TiO2 結合 core-shell (TiO2-iron oxide/Fe0)，具有自發性電池效應，並且可產生 OH 自由基與 H2O2形 成 Fenton 反應。
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2. NTFC 處理有機物應用與機制
(1) NTFC 證實具有延長零價鐵反應與增進 TiO2效能特性，並且對於高 色度廢水處理效率非常高。
(2) NTFC 材料中的 TiO2確實能在 UV 光的激發下，有效提供電子來還原 系統中的三價鐵，維持系統處於高二價鐵低三價鐵的優勢情況，而增 進與延長零價鐵使用效能。
(3) 電化學腐蝕測試，得知 TiO2可以幫助延緩零價鐵表面氧化並且維持 效能，有助於解決無法 Fe0於工廠製備後才運送之限制，可增加零價 鐵之運用性。
(4) NTFC 由於為零價鐵與二氧化鈦作用所以自由基產生量於反應約比 純零價鐵同劑量生成量高 2 倍，而 NTFC 雙氧水生成趨勢與零價鐵 相似，但是濃度約 nZVI 的 4.8 倍，而 NTFC 產生二價鐵濃度比零價 鐵高，所以 NTFC 反應性比零價鐵好。
(5) NTFC 第一階段起始反應前段為與零價鐵相似之還原反應，NTFC 第 二段反應為氧化反應，第三階段反應 NTFC 表面產生 core shell 氧化 態表面並形成自發性電池效應與 Fenton 反應。
(6) 偶氮染料為生物難分解有機物，經由 NTFC 反應後，發現 NTFC 反 應快速，而總有機碳去除速率較慢，中間產物分析發現原始結構很快 速被破壞，並產生易於生物分解之小分子物質，廢水的可生物分解利 用性增加，NTFC 反應可做為生物氧化之預處理技術。
7-2 建議
本論文所研究為實驗室規模與純化條件及實廠廢水性質差異極大，因此
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未來還有尚待釐清與待完善之處，未來可以以下幾方面著手研究〆
(1) NTFC 複合材料可就材料研發更比例與品質完善之材料，並研發於 UV-B 與 UV-C 激發之可見光材料，並提高系統中過氧化氫之利用率，
以降低處理成本。
(2) 由於 NTFC 研究為實驗室規模階段，未來可以進行模廠或處理實際廢 水，研究中以實驗室規模磁力回收 NTFC，未來研究可以其他電磁方 式回收並進行更深入回收與再利用探討。
(3) 由於 NTFC 需要以 UV 光激發，雖然研究中可以經由可見光激發，未 來可以研發改良更接近 UV-C 激發之觸媒材料。
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