English  |  正體中文  |  简体中文  |  Items with full text/Total items : 51491/86611 (59%)
Visitors : 8252905      Online Users : 84
RC Version 7.0 © Powered By DSPACE, MIT. Enhanced by NTU Library & TKU Library IR team.
Scope Tips:
  • please add "double quotation mark" for query phrases to get precise results
  • please goto advance search for comprehansive author search
  • Adv. Search
    HomeLoginUploadHelpAboutAdminister Goto mobile version
    Please use this identifier to cite or link to this item: http://tkuir.lib.tku.edu.tw:8080/dspace/handle/987654321/36000


    Title: 多管式微波消化法快速偵測化學需氧量
    Other Titles: A study of multichannel method for rapid determination of chemical oxygen demand using microwave digestion
    Authors: 丁裕樵;Ting, Yu-chiao
    Contributors: 淡江大學水資源及環境工程學系碩士班
    許道平;Hsu, Tau-being
    Keywords: 化學需氧量;微波消化;分光光度法;chemical oxygen demand;microwave digestion;spectrophotometry
    Date: 2007
    Issue Date: 2010-01-11 07:27:18 (UTC+8)
    Abstract: 本研究係繼續改進微波消化法,建立一套簡易的微波加速反應系統裝置。將試劑與樣品混合以鐵氟龍幫浦注入微波爐內腔之鐵氟龍反應管中,以多管路系統替代單一管路進行多樣品同時進行微波消化,微波氧化反應完成後,將樣品流經冷卻系統迅速冷卻,並連接至收集瓶中,經由PVDF之注射過濾頭過濾以及離心過濾後,再連接至分光光度計內光徑10 mm之穿流式石英槽,偵測600 nm 之溶液吸光度,比對COD標準品製備之檢量線,測得水樣之化學需氧量。
    實驗第一部分建立最佳化實驗條件(微波功率、時間、反應管長度),實驗結果顯示,單一管路系統微波消化最佳化實驗條件為混合消化液2 mL ( 0.0347 M重鉻酸鉀溶液0.6 mL 及0.55% 硫酸銀 溶液1.4 mL );1 mL之水樣。微波功率453 W以及消化時間35秒。此系統最佳化測試所得之100-900 mg/L之檢量線與密閉迴流法建立之檢量線加以比對分析,各濃度偵測之吸光度差異性小,檢量線線性關係良好。
    第二部份則進行系統改進,以六向抗壓閥取代原本之控制閥,並增加三向分流閥進行清洗程序與氮氣吹除、收集酸氣中和,以增加系統偵測效果與安全性,進行系統清洗程序測試,最佳化清洗與淨化程序為注入1 N硝酸溶液30秒,再以試劑水清洗系統管道30秒,再注入氮氣30秒(50 psi)吹除系統管道內殘餘水分。
    第三部份將單一管路增加為多管路反應系統,進行多管路同一時間微波加熱反應,實驗結果顯示:多管式微波消化系統最佳化實驗條件為混合消化液2 mL ( 0.0347 M,0.0104M重鉻酸鉀溶液0.6 mL 及0.55% 硫酸銀溶液1.4 mL );1 mL之水樣,微波功率453 W以及消化時間120秒,並建立100-900 mg/L與0-200mg/L之檢量線,其線性關係良好。
    分別以多管微波消化法與密閉迴流法進行模型化合物溶液測試回收率,微波消化效果較傳統加熱方式佳,水樣之氯鹽干擾的測試方面,以不添加硫酸汞之方式,可有效抑制3000 mg/L 以下氯鹽之干擾。方法偵測極限為14 mg/L(0.0347 M重鉻酸鉀溶液);21 mg/L(0.0104 M重鉻酸鉀溶液)。以APG盲樣測試,其精密度與準確度在4%以下,環檢所盲樣測試下,精密度為8 %;準確度為14 %。分別針對16種真實水樣進行測試,分別以微波消化法、密閉迴流法進行實驗,再以注射過濾方式或離心過濾方式做比較,實驗結果顯示,以注射過濾方式處理印染整理、造紙、畜牧業(二)、金屬基本工業、醱酵與化工產業放流水之水中氯鹽,其偵測結果微波消化法與密閉迴流法平均測值相對誤差於7 %以下,而以離心過濾方式處理製革、造紙、畜牧業(一)放流水、食品廢水與染料廢水之水中氯鹽,其兩者相對誤差於5 %以下。可見離心過濾方式效果較佳。經由實際水樣測試結果顯示多管微波消化法與密閉迴流法之測試結果之相對誤差均在於10%以下。
    A simple multichannel method for rapid determination of chemical oxygen demand (COD) using microwave digestion system to replace the conventional open reflux method is proposed. The method based on use of a modified microwave heating oven to accelerate the rate of the digestion step is described. This method consists of a first digestion step where the samples and oxidants in Teflon coil (five coils at a time) are heated by the microwave radiation and a second one where the Cr3+ in digested sample after being filtered is determined by the spectrometry.
    The aim of this study is to develop the method a very rapid and waste-less method for determination of COD by spectrophotometer. Only 2 mL of the mixed solution containing 1.4 mL 0.0347 M K2Cr2O7 solution, 0.6 mL 0.55 % Ag2SO4 solution and 1 mL sample are required for the digestion. The optimal heating condition of the multichannel method is microwave power 453 W and reaction time 120 seconds.
    A detection limit of 14 mg/L, relative standard deviation of 5%, the linear rang of 100~900 mg/L, excellent tolerance for interferences (chloride ion does not interfere at 3000 mg/L even in the absence of HgSO4 and AgNO3) are some of most significant features of the method, which has been exhaustively validated as follows (a) application to solution also analyzed using standard method (b) validation using the certified reference materials as APG quality standard tests and proficient tests (E.P.A R.O.C.). The proposed method is cost-effective, save time, energy and reagents with providing precise results for the pure organic compounds and wastewater samples.
    Appears in Collections:[水資源及環境工程學系暨研究所] 學位論文

    Files in This Item:

    File SizeFormat
    0KbUnknown218View/Open

    All items in 機構典藏 are protected by copyright, with all rights reserved.


    DSpace Software Copyright © 2002-2004  MIT &  Hewlett-Packard  /   Enhanced by   NTU Library & TKU Library IR teams. Copyright ©   - Feedback