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年度	103	專案性質	實驗性質
專案類別	研究專案	研究主題	整治
申請機構	元智大學化學	申請系所	工程與材料科學學系
專案主持人	林錕松	職等/職稱	教授
專案中文名稱	利用奈米零價鐵微粒去除DNAPLs含氯有機污染物之技術研發及地下水污染場址整治工程評估
中文關鍵字	奈米零價鐵微粒；比水重之非水相含氯有機物污染物；直接注入法；地電阻顯影儀；還原分解；整治評估
專案英文名稱	Technical Development for Decontamination of DNAPLs Chlorinated-contained Organics by Zero-Valent Iron Nanoparticles and Evaluation for In-situ Remediation on Groundwater Contaminated Sites
英文關鍵字	Zero-valent iron nanoparticle；Dense non-aqueous phase liquid chlorohydrocarbons；Directly injection method；Resistivity image profiling；Reductive decomposition；Remediation evaluation
執行金額
執行期間	2013/11/25 至 2014/11/24
計畫中文摘要	隨著台灣科技工業的發展，在眾多工業製程中，含氯有機化合物因具有特殊物化特 性，因此被廣泛使用。而近年來意外排放和使用過程中不當處置，造成含氯有機化合物 大量進入土壤和地下水層中，且含氯有機化合物具有毒性，對人體更具有致癌性及致基 因突變性，因此對環境的衝擊格外受到重視。本研究之主要目的是探討利用化學還原法 製備奈米零價鐵顆粒(zero-valent iron nanoparticles, ZVINs)，經由表面包覆有機分子使 ZVINs 懸浮於水相中並將其應用於受 DNAPL 污染物污染之現地場址整治，其結果藉由 場發掃描式電子顯微鏡(FE-SEM)、X 光粉末繞射儀(XRD)及穿透式電子顯微鏡(TEM)測試 檢測 ZVINs 懸浮溶液與 DNAPL 污染地下水體反應後之變化與結構分析，以期望進一步 了解利用ZVINs懸浮溶液及地電阻顯影儀(RIP)處理現地場址污染地下水體之效能及可行 性。 在實驗部分，實驗室中所合成之 ZVINs 顆粒於氬氣下經燈罩法烘乾並惰化後 XRD 圖譜文獻資料相符，且自行合成之 ZVINs 顆粒在 FE-SEM 圖中為粒徑為 20~50 nm 之球 形顆粒；而經聚乙基亞胺(PEI)改質後之 ZVINs 顆粒其 XRD 圖譜文獻資料相符，但在 2θ = 34.36 處多出一與 PEI 鍵結後之訊號，而由其 FE-SEM 圖可判定經 PEI 改質後之 ZVINs 顆粒粒徑在 50~80 nm 間，較未改質之前小。將表面包覆 PEI 之 ZVINs 懸浮溶液利用直 接注入法應用於現址受污染場址試驗中，於注入後場址內各井位之 7 種主要 DNAPL 污 染物濃度均呈現降低的趨勢，可見表面包覆 PEI 之 ZVINs 懸浮溶液隨著地下水流動至污 染物殘留層將 DNAPL 污染物還原成無毒害之產物。此外，於實驗室中利用 ZVINs 懸浮 溶液與各井污染地下水體模擬現址反應後，由其測驗之結果與地下水管制項目及管制標 準比較後，7 種主要有機污染物其濃度經處理 1 天後濃度也大幅降低，甚至低於飲用水管 制標準值，其結果與現地場址試驗結果相符。由實驗室中 ZVINs 處理各井位抽取污染水 樣試驗之 FE-SEM 及 TEM 分析，可知未改質之 ZVINs 顆粒反應後其粒徑大小在 20~50 nm 之間且聚集嚴重，而表面經 PEI 高分子包覆改質之 ZVINs 顆粒其粒徑大小在 50~80 nm 之間。XRD、ESCA 及同步輻射分析中未改質或改質之 ZVINs 顆粒與污染水樣反應一天 後氧化為 Fe3O4。可見在現場水井投入 ZVINs 懸浮液後，部分污染物濃度已明顯降低。 實驗室測出之導電度趨勢與地電儀影樣圖判定結果相符，顯示投入之 ZVINs 懸浮液，確 實已在地底下隨著水流移動，進而和污染物 plume 作用。由施測結果可知，表面 PEI 改 質後 ZVINs 懸浮溶液與 DNAPL 污染物產生之氧化鐵為低導電率，表示地層中電阻率增 加亦有表面 PEI 改質後 ZVINs 懸浮液，與 DNAPL 反應而還原降解所造成。本計畫已初 步建立 ZVINs 粉體及地電阻顯影儀現址處理地下水污染之完整操作程序及技術，進而提 升國內地下水污染之現址處理技術，並可做為日後污染場址的整治復育之參考，落實整 治技術之本土化目標。
計畫英文摘要	In Taiwan, remediation of sites contaminated by dense non-aqueous phase liquids (DNAPLs), especially chlorinated organic compounds, is a significantly priority in the environmental field because of their widespread use in many applications. Therefore, the main objectives of the present study were to prepare surface-modified zero-valent iron nanoparticles (ZVIN) by coating polyethyleneimine (PEI) nanofilms and in-situ DNAPLs-contaminated groundwater remediation. Characterization of ZVIN or PEI/ZVIN reacted with DNAPLs-polluted groundwater were also investigated by field emission-scanning electron microscopy (FE-SEM), X-ray powder diffractometer (XRD), transmission electron microscopy (TEM), electron spectroscopy for chemical analysis (ESCA) and resistivity image profiling (RIP). In addition, field tests of this study were also carried out to provide information concerning the removal efficiencies and feasibilities in the chemical reductive treatment processes for DNAPLs contaminated sites, and determined if further developments would be warranted. Experimentally, from FE-SEM microphotos and TEM images, spherical ZVIN with a diameter of 20-50 nm were measured. ZVIN having a strong characteristic peak of PEI at 2θ = 34.36 was investigated by XRD patterns. The specific surface area of ZVIN measured by BET isotherms is 34.7 m2 /g. From ESCA spectra, the proportion of Fe/O is 1.33 on ZVIN surface including the main species of FeO, Fe3O4, and FeSO4. In addition, ZVIN coated with PEI (PEI/ZVIN) in the form of spherical particles with a diameter of 50-80 nm were also measured by FE-SEM and TEM microphotos. PEI/ZVIN has a strong characteristic peak of Fe(0) at 2θ = 44.83 identified by XRD patterns and surface area of 53.4 m 2 /g measured by BET isotherms was also investigated. From ESCA spectra, the proportion of Fe/O is 0.39 on PEI/ZVIN surface including the main species of Fe3O4 and FeSO4. By using resistivity image profiling (RIP), the conductivity data of modified ZVINs solution and sampling groundwater were similar. It indicated that lower conductivity of FeO species was found. Obviously, the data of in-situ remediation indicated that concentrations of DNAPLs after using well-injection method were notably reduced. In addition, RPI can elucidate complex subsurface DNAPLs structures by dense sampling of resistivity variation at shallow depth. The combinative technology of floating surface-modified ZVINs and RIP technique would be economically and environmentally attractive. Furthermore, the simulation calculation, basic engineering design, and economic estimation of this in-situ remediation technique were also performed to develop a domestic in-situ remediation technology in the near future.