| 摘要: | 本研究使用芬頓、電芬頓、光電芬頓程序進行對-乙醯氨基苯酚之降解試驗。以新型電芬頓及光電芬頓程序可減少亞鐵之使用量，並且降低反應過程中鐵汙泥之形成，對於污染物之去除效率也有顯著提升。
在過去十年中，人類、獸用藥品及個人護理用品(PPCPs)以被受到關注，因為PPCPs維持久性有機污染物且已被發現在我們所生活的環境中。這些新出現的污染物不斷的在環境中被發現。PPCPs分別從以下途徑進入我們的生活中，包括製造工廠的排放、在家庭及醫院直接拋棄之過剩藥物、人類及動物使用藥後之排泄物及養殖場之水。現有的數據顯示，這類藥物可改變魚類的內分泌系統及對於有毒藻類和無脊椎動物皆可能發揮其作用，且有利於微生物之繁衍。
在一般傳統的汙水處理廠對於PPCPs破壞僅有非常低的效率，因為PPCPs通常耐生物降解，因此這意味者必須使用氧化技術來確保其從環境中去除。化學氧化劑如氯氣、二氧化氯、臭氧等方法能與藥物代謝，但並不能促進其徹底礦化。因此使用高級氧化程序進行藥物之降解。在使用紫外線燈及電流可以有效的增加Fenton程序之處理效率，稱為光電芬頓程序。
在PPCPs中，使用最廣泛及使用最大量為對-乙醯氨基苯酚(Acetaminophen, ACT)，也就是俗稱的普拿疼，因此選為這項研究中之目標化合物。
初始pH值(pHi)、亞鐵離子、過氧化氫濃度為芬頓之重要參數，三種參數對於不同芬頓程序皆有很大影響。亞鐵離子濃度從0.01mM增加至0.1mM，氫氧自由基之含量提升，且增加了對-乙醯氨基苯酚之去除效率及速率。
降解ACT之最佳條件為過氧化氫濃度為25mM、亞鐵離子0.1mM、pH 3，可在40分鐘完全去除污染物，分別使用芬頓、電芬頓、光電芬頓程序之COD去除效率為34%、38%、40%。最終TOC去除率分別為14%、23%、23%。
A new approach for increasing ferric reduction efficiency using different electro-Fenton and photoelectro-Fenton processes has been developed to degrade organic toxic contaminants. Over the past decade, human and veterinary Pharmaceuticals and Personal Care Products (PPCPs) have received increasing attention as POPs in waters. These emerging pollutants are continuously introduced into the aquatic environment at ng-μg L-1 levels by several routes including emission from production sites, direct disposal of overplus drugs in households and hospitals, excretion from drug-using human and animals, and water treatments in fish farms.
There are some available data indicating that some drugs can alter the endocrine system of fish as well as exert toxic effects on algae and invertebrates, even benefit the proliferation of multiresistant strains of microorganisms. The common conventional sewage treatment plants provide low efficient destruction to PPCPs because they are usually resistant to biodegradation, which means the adoption of oxidation technologies is needed due to it can ensure PPCPs being removed from the environment. Chemical oxidants such as Cl2, ClO2, and O3 can react with drugs and their metabolites, but they are unable to promote the mineralization completely.The use of UVA light and electric current as electron donors can encourage the efficiency, which named the Fenton reaction.
Acetaminophen (ACT) is the target compound in this study because it was used with extensive, considerable quantities. Effects of initial pH (pHi), Fe2+ loading, H2O2 concentration are determined by the photoelectro-Fenton process. Increase the ferrous ion concentration from 0.01 to 0.1mM leading to increase the hydroxyl radicals, and then raising the degradation efficiency of ACT. The optimal H2O2 concentration for ACT degradation in this study is 25mM.
The final COD removal efficiencies are 34%, 38% and 40% using Fenton, electro-Fenton and photoelectro-Fenton processes, respectively. The final TOC removal efficiencies are 14%, 23% and 23% using Fenton, electro-Fenton and photoelectro-Fenton processes, respectively. |
