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年度	100	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	申請系所	化學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	利用奈米零價鐵還原降解受TNT、RDX及HMX高能火炸藥污染水體及現址整治工程技術評估之研發
中文關鍵字	"奈米零價鐵、高能火炸藥、還原降解
專案英文名稱	.
英文關鍵字	Zero-valent iron nanoparticle；High-eexplosives；Reductive degradation
執行金額
執行期間	2011/11/26 至 2012/11/25
計畫中文摘要	"由於台灣地小人稠，高能火炸藥(TNT、RDX及HMX)在製程中之廢水極可能排放於周遭環境中，常常造成土壤及地下水的污染，此污染物對人體及生態具高毒性且難以從環境中降解去除，故環保且有效的處?受高能火炸藥污染的土壤及水體的技術，即成為現今技術研發之重要課題。因此，本研究計畫之主要目為利用化學還原法製備奈米零價鐵顆粒(ZVINs)，加以表面改質後，應用於處?因高能火炸藥三硝基甲苯(TNT)、海掃?(RDX)及奧特更(HMX)污染土壤及地下水體；另外，本研究更?用?米?價鐵觸媒對火炸藥污染去除，提供工程技術放大及經濟上有效之處?技術與研究成果。本計畫研究內容可分為三大部分：第一部分完成藉由自?合成及表面改質ZVINs微?，並以精密儀器測定奈米Fe(0)之晶相、價數表面積及孔?分析及與火炸藥反應後之表面分析及?屬氧化物種?，探討Fe(0)還原火炸藥之途徑；第二部份完成以液相層析串聯質譜儀(LC/MS/MS)，探討受污染水體中高能火炸藥之降解效率、反應動力參數、熱力學模式及反應途徑；第三部份完成利用貴重精密儀器，例如：FE-SEM、XRD、ESCA/XPS、TEM、BET比表面積測定儀(ASAP)及同步輻射(XANES/EXAFS)分析，鑑定ZVINs反應前後結構特性及產物之差異性，後續將深入瞭解表面改質前後ZVINs還原降解反應高能火炸藥之機制及途徑，並探討處理含火炸藥土壤、廢水或地下水之界面化學及反應機制，以利提升去除含火炸藥污染之土壤、廢水或地下水之效果；另外，亦完成進行ZVINs批式與管柱測試處理系統，以利後續經濟效益評估或基本工程放大設計之參考。本計畫研究重點成果分別說明如下： 1. 已完成收集火炸藥特性、污染源、污染現況及彙整目前國內外有關奈米零價鐵粉及表面改質分散技術之相關資料； 2. 已完成奈米零價鐵粉合成方法及結構特性分析鑑定； 3. 已完成PEG改質奈米零價鐵粉之最佳表面改質與粉體分散技術； 4. 完成建立PEG表面改質前後奈米零價鐵粉處理含火炸藥溶液之批式/連續式管柱系統之反應動力參數及最佳反應操作條件； 5. 已完成使用XRD、FE-SEM/EDS及TEM分析鑑定PEG表面改質前後奈米零價鐵粉表面及晶體結構特性之差異；並利用EXAFS光譜研究鐵原子結構(鍵距或配位數)，另以XPS/Auger及XANES光譜分析表面改質前後奈米零價鐵微粒之氧化價數及種類； 6. 實驗中，由穿透式電子顯微鏡(TEM)分析可明顯發現，在奈米零價鐵微粒表面上有5~10 nm之PEG高分子膜。 7. 由FE-SEM分析其粒徑為20~50 nm，BET量測其比表面積為42.557 m2 g-1。降解研究中，以0.1 g之nano-Fe(0)降解3種高能火炸藥水溶液，實驗結果顯示在室溫下(25 ± 1℃)於1 h內可完全降解90 ppm之TNT、35 ppm之RDX及5 ppm之HMX。在動力學研究中，將nano-Fe(0)降解三種不同濃度高能火炸藥實驗結果代入簡化的Langmuir-Hinshelwood動力學模式ln(C0/Ca) = kt計算得到R2 > 0.995，其降解反應為一階反應。在熱力學模式研究中，則是以三種不同的高能火炸藥於25及35℃的溫度下進行實驗，並以Arrhenius equation計算其活化能，得到TNT、RDX及HMX的活化能分別為9.743、10.079及12.460 kcal mol-1。 8. 奈米零價鐵降解高能火炸藥反應性結論：在奈米零價鐵降解高能火炸藥的反應性研究中，發現由高能火炸藥的結構中接NO2官能基團元素推、拉電子能力、立體結構障礙及官能基數目，在立體結構障礙中，TNT因具苯環結構，其立體結構是平面的，在RDX的立體結構上是為三氮六環，其立體結構最穩定為椅型結構，HMX的立體結構是為四氮八環，其立體結構最穩定為皇冠型結構，其立體障礙為HMX > RDX > TNT，在硝基鍵結的拉電子能力與官能基的數目與反應速率研究中，拉電子的能力越強與官能基的數目越多就越不容易進行還原取代，在TNT中結構中硝基團接的元素為C，RDX及HMX硝基團接的元素為N，又N的陰電性(3.0) > C (2.5)，N拉電子的能力> C，可以得知反應速率應為TNT > RDX、HMX，在官能基的數目部份HMX比RDX多出一組NO2，故其反應速率應為TNT > RDX > HMX，與實驗結果相符。 9. 奈米零價鐵降解高能火炸藥反應途徑及中間產物結論：奈米零價鐵降解高能火炸藥的反應途徑研究實驗中，是以三種不同的高能火炸藥進行研究，並以LC/MS/MS及GC/MS鑑定其中間產物。由實驗發現(1)TNT反應中間產物是趨向於NO2官能基團被取代NH2的單取代反應、(2)RDX反應中間產物是趨向於NO2官能基團被取代不同數量的NO，其取代的趨勢為單取代 > 雙取代 > 三取代及(3)HMX反應中間產物是趨向於NO2官能基團被取代不同數量的NO後再進一步被還原為NH2。在以上數種不同中間產物會因NO2官能基團被還原為NO或NH2，將導致結構不穩定而開環水解作用形成長鏈烷類、methylenedinitramine以及bis-nitroamine，之後會再降解到formaldehyde、methanol、hydrazine和dimethyl hydrazine，這些中間產物最後分解成N2O、CH4和CO2。 "
計畫英文摘要	"In the recent years, soil, wastewater and groundwater are polluted by explosives-contaminated wastewaters discharged from military factory worldwide. These high-explosives are toxic to human beings/ecosystems and very difficult to be removed from the environment. Therefore, a highly efficient and clean method was developed utilizing zero-valent iron nanoparticles (ZVINs) to reduce the explosives-contaminated groundwater. Experimentally, The LC/MS/MS technique was used to determine the efficiency of degradation, kinetic model, thermal model, activation energy, and reaction pathways for ZVINs degradation of high-explosives. Nanophase zero-valent iron powders were surface-modified and then enhanced the efficiency of reduction by adding polyethylene glycol (PEG) nanofilms. The lab-scale batch ZVINs reactor system was conducted and tested. Moreover, the properties of ZVINs before or after degradation were also analyzed. The morphology and crystallinity of ZVINs, fine structures, oxidation states of metals in ZVINs were also investigated with XRD, TEM, FE-SEM/EDS, XPS/ESCA, and EXAFS/XANES techniques. In addition, analyses of these experimental data, optimal operations, conversion, mechanism, basic engineering design of abatement technologies, and economic estimation of a lab-scale column reductive ZVINs reactor was also tested for further on-site or industrial performance and development. Therefore, outcomes of this project were comprised of the major results shown as following: 1. The tasks of survey the kinds, sources, amounts, distribution, properties, abatement technologies, and impact risks of explosives species in soils, wastewaters or groundwater were already finished; 2. Establishment of the ZVINs synthetic procedures and determine the surface or fine structural properties of ZVINs have been finished; 3. Establishment of the optimal surface-modification using PEG thin film and well suspension/dispersion technology of ZVINs have been achieved; 4. Obtaining of the optimal operations of a lab-scale batch column reduction reactor using ZVINs for the removal of explosives species in groundwater were finished; 5. Primary determination of the morphology, crystallinity, fine structures, oxidation states of ZVINs before and after used for the removal of explosives contaminants in groundwater for a lab-scale batch reactor by XRD, FE-SEM/EDS, TEM, EXAFS, XPS/Auger or XANES spectroscopy have been achieved; 6. Experimentally, ZVI nanoparticles of this proposed study were prepared by borohydride reduction method at room temperature and ambient pressure. The surface of ZVI nanoparticles was coated with 5~10 nm thin film of polyethylene glycol (PEG) measured by TEM microphotos; 7. Zero-valent iron nanoparticles with a diameter of 20-50 nm and specific surface area of 42.56 m2g-1 were measured by FE-SEM and BET. Zero-valent iron nanoparticles had a strong characteristic peak at 2θ = 44.6o were investigated by XRPD patterns. In the degrading experiments, 90 ppm TNT, 35 ppm RDX and 5 ppm HMX at room temperature (25 ± 1℃) were degraded completely with 0.1 g zero-valent iron nanoparticles in 1 h. The experimental results were placed into a simple Langmuir-Hinshelwood equation (ln(C0/Ca) = kt) and the R-squares were all upon 0.995. However, the degradation statistics corresponded to the pseudo first order kinetics. The thermodynamics study was carried on three different high-explosives under 25-35℃ and the activation energies of TNT, RDX, and HMX were calculated to 9.74, 10.08, and 12.46 kcalmol-1 by Arrhenius equation, respectively; 8. The reductive kinetic rates of high energy explosives contaminants are TNT > RDX > HMX. Based on the different ring structures of TNT, RDX, and HMX, the NO2 functional group and bezenene group of TNT, three N of six ring for RDX, and three N of eight rings for HMX structures make the different stabilities of these explosives contaminants; 9. The mechanisms and products/by-products of TNT, RDX, and HMX explosives contaminants reductive degradation onto ZVINs were investigated by using HPLC/MS/MS techniques. The intermediates of TNT, RDX, and HMX degradation onto ZVINs were from NO2 converted into NO and then converted into NO or NH2. The products or by-products were hydrolysed from alkenes, methylenedinitramine, and bis-nitroamine, and further degradated to formaldehyde, methanol, hydrazine, and dimethyl hydrazine. These intermediates were also decomposed into N2O, CH4, and CO2。 "