以實驗結合量子化學理論：探討非離子界面活性劑之光催化反應

Combining quantum chemical programs with experiments: a discussion of the photocatalytic reaction of non-ionic surfactant NPnEO

游林祺(Lin-Qi You)

指導教授 ： 陳孝行

國立臺北科技大學/工程學院/環境工程與管理研究所/碩士(2011年)

https://doi.org/10.6841/NTUT.2011.00419

摘要

壬基苯酚聚乙氧基醇類(NPnEO)為工業製程中使用最廣之非離子界面活性劑，其流佈於環境中經微生物作用將形成不易分解且具環境荷爾蒙特性之其它NP類副產物。而NPnEO以一般生物處理之效率不彰且亦會產出NP，因此，本研究即應用量子化學程序ChemBioOffice2008中之半經驗方法(Semi-empirical)，計算NP9EO分子之表面電子密度與點電荷(Calculate by PM3)，而後配合光觸媒催化反應討論其氧化與礦化程度，可進而闡述NP9EO於光催化反應中之行為機制及反應路徑預測，並藉此方法希望發展出處理環境中NPnEO之可行且有效處理技術。
本研究以光觸媒(DP-25與N/Fe-TiO2)協同UV光與可見光對NP9EO進行光催化反應，且在實驗進行前首先利用STATISTICA統計軟體對各項實驗參數做一實驗設計(Designed by Central Composite Design)。根據CCD設計產生之實驗分別於DP-25與N/Fe-TiO2找到一最佳光催化NP9EO效率組(DP-25，pH3.5，光觸媒濃度0.5g/L，槽體轉速300RPM)及(N/Fe-TiO2，pH4，光觸媒濃度1g/L，槽體轉速450RPM)，其NP9EO分解率均達78%以上(礦化程度43%以上)。
而後將不同反應時間點之水樣以GC-MS分析後結合應用量子化學程序，建構出NP9EO於一連串光催化過程中，其主要之三列反應路徑，並確認在240分鐘光催化反應後其最初副產物(NPnEO、NPnEC等)皆分解為對環境無害之低分子量物質(2-(vinyloxy)ethanol、Stearic acid及Diethoxymethane等)，以及最終達到礦化之目的。

關鍵字

量子化學程序 ； 半經驗方法 ； 反應路徑 ； 光觸媒

並列摘要

NPnEO is the non-ionic surfactants which were most commonly used in industrial processes. When disseminated in the environment, other NP-products category will be formed by the mechanism of microorganisms. Such substances can not be easily decomposed in the water environment and have the characteristics of environmental hormones.
General biological treatment is not very efficient, and it will produce NP too. Therefore, this study used photocatalyst to trigger a photocatalytic reaction on NPnEO, explored the intermediates during the photocatalytic reaction, and discussed the changes in the follow-up mechanism. Finally, by this method, this study expects to develop effective treatment technology of NPnEO in the environment.
This study calculated Frontier electron density and point charge by semi-empirical method in quantum chemistry programs (ChemBioOffice2008), and together with the GC-MS analysis, discussed the oxidation and mineralization efficiency of NPnEO. With the combination of the above methods, the reaction mechanism can be explained, and a photocatalytic reaction pathway of NPnEO is proposed.
Before the NPnEO photocatalytic reaction(by DP-25 and N/Fe-TiO2), this study used the statistical software(STATISTICA) to take the experiment design(Designed by Central Composite Design).
According to CCD experiment design, it was found that the best efficiency parameters were pH3.5, photocatalyst concentration:0.5g/L, rotation speed:300RPM for DP-25 and pH4, photocatalyst concentration:1g/L, rotation speed:450RPM for N/Fe-TiO2. By the above experiment, NPnEO degradation efficiencys were higher than 78%(more than 43% organics were mineralization).
After the NPnEO water samples(of different reaction time) were collected, this study constructed the three main reaction pathway of NPnEO in photocatalytic process that combined with GC-MS analysis and quantum chemical programs. It also confirmed that after the 240 minutes photocatalytic reaction, the initial intermediates (NPnEO, NPnEC, etc.) were broken down into low molecular weight substances(2 - (vinyloxy) ethanol, stearic acid and diethoxymethane, etc.), and ultimately achieve the purpose of mineralization.

並列關鍵字

Quantum chemistry ； Semi-empirical ； Pathway ； Photocatalyst

參考文獻

9. 王鳳英, 界面活性劑的原理與應用，:高立圖書. 1998.

24. Bursch, W., M. Fuerhacker, M. Gemeiner, B. Grillitsch, A. Jungbauer, N. Kreuzinger, E. Moesti, S. Scharf, E. Schmid, S. Skutan, and I. Walter, Endocrine disrupters in the aquatic environemtn: The Austrian approach - ARCEM. Water Science and Technology, 2004. 50(5): p. 293-300.

1. Di Gioia, D., et al., Nonylphenol polyethoxylate degradation in aqueous waste by the use of batch and continuous biofilm bioreactors. Water Research, 2009. 43(12): p. 2977-2988.

2. Horikoshi, S., et al., Photodecomposition of a nonylphenol polyethoxylate surfactant in a cylindrical photoreactor with TiO2 immobilized fiberglass cloth. Applied Catalysis B: Environmental, 2002. 37(2): p. 117-129.

3. Chen, L., H.-y. Zhou, and Q.-y. Deng, Photolysis of nonylphenol ethoxylates: The determination of the degradation kinetics and the intermediate products. Chemosphere, 2007. 68(2): p. 354-359.