應用二氧化鈦奈米管陣列光電催化檢測化學需氧量之研究

A Photoelectrocatalytic Method Using Titanium Dioxide Nanotube Arrays for Chemical Oxygen Demand Determination

邱信豪(Sin-Hao Ciou)

指導教授 ： 王文裕

朝陽科技大學/理工學院/環境工程與管理系/碩士(2012年)

摘要

化學需氧量 (Chemical oxygen demand, COD) 是主要的水質監測項目
之一。目前檢測 COD 的標準方法主要為重鉻酸鉀法 (CODcr
)；但該法分
析時間長且繁瑣、容易產生二次污染；因此無法因應即時水質監測需求。
由於二氧化鈦優異的物理、化學、光學等性質，讓二氧化鈦成功地被應用
於光觸媒反應。本研究利用二氧化鈦奈米管陣列膜，與白金電極、甘汞電
極，組裝成三電極光電催化反應系統。此反應系統之 UV 光源與二氧化
鈦膜間距為 1 cm、光強度 20 mW/cm
2
；並以不同實驗變因 (包括偵測時
間、外加電壓、pH、氯鹽濃度)，在不同濃度的標準品模擬廢水中測試其
光電量對 COD 濃度之變化。結果顯示，光電量會隨著溶液濃度 (10 - 300
mg/L) 增加而增加，在外加電壓 0.4V、偵測時間 10 秒、pH 4 - 10 時，
抗氯鹽干擾濃度可達 600 mg/L，達到最佳操作條件。本研究並對三電極
光電催化反應系統系統進行性能評估，結果顯示，穩定性 0.3 %、再現性
0.9 %、偵測極限 0.6 mg/L。最後，並以真實廢水驗證本系統的可用性，
結果顯示真實廢水以光電催化所得之光電量，經標準校正線所對應的
COD，與真實廢水 CODcr 的相關線性達 0.996。顯示本系統適用於產業
廢水排放之放流水化學需氧量之快速檢測。

關鍵字

光電催化 ； 化學需氧量 ； 化學感測器 ； 二氧化鈦奈米管

並列摘要

Chemical oxygen demand (COD) is one of the main items of water quality
monitoring parameters. The standard method for the detection of COD is
potassium dichromate method (CODcr
). The standard dichromate chemical
oxygen demand (COD) method is a time-consuming and tedious and prone to
the shortcomings of secondary pollution. The standard method can not be
timely monitoring Demand. due to superior physical, chemical, and optical
properties, titanium dioxide has been successfully applied to photocatalytic
reaction. In this study, used a TiO2 nanotube arrays film, a platinum electrode
and a calomel electrode to setup a three-electrodes photoelectrocatalysis
reaction system. In this photoelectrocatalytic system the fixed spacing between
UV lamp and TiO2 is 1 cm and light intensity is 20 mW/cm
2
. A constant
potential coulometry method was applied to determine various COD values of
different concentrations of standard solution with different experimental
variables (such as detection time, applied voltage, pH, and chlorine ion
concentration). The experimental results show that the detected coulombs
increase with the COD concentration (10 - 300 mg/L) increased.The best
detection parameters are 0.4 V of applied voltage, 10 seconds of detection time
and solution pH 4 – 10. At the meantime up to 600 mg/L of molestation
chlorine ions of were dispelled. The performances of the three electrode
reaction system were also evaluated. The results show 0.3 % of stability, 0.9 %
of reproducibility and 0.6 mg/L of detection limit. Finally, availability of this
system to the true waste water was also verified. The detected coulombs by the
constant potential coulometry method with different domestic industrial
wastewaters were corresponds to corrected line of standard CODcr and a linear III
relationship (R
2
= 0.996) was found. The results reveal this system is suitable
for the fast detection of COD in effluent of various industrial wastewater.

並列關鍵字

Chemical oxygen demand ； titanium dioxide nanotube ； photoelectrocatalysis ； chemical sensor

參考文獻

王國華，“以 UV/TiO2 程序處理氣相中三氯乙烯之研究”，國立中興大學

唐政宏，探討二氧化鈦觸媒電極氫氧自由基產率及處理生活污水效率，朝

Ai, S., Li, J., Yang, Y., Gao, M., Pan, Z., Jin, L., “Study on photocatalytic

oxidation for determination of chemical oxygen demand using a

Water and Wastewater(18th ed.), American Public Health Association,