鐵驅動的高級氧化過程降解新興污染物奎寧和萊克多巴胺：共存螯合劑對處理效率的影響

Abstract

近年來，新興污染物被定義為「尚未確定或確認」、「不受管制」和「對人類健康和環境構成風險」的化學污染物。現有污水處理廠和淨水廠的處理單元也無法有效去除這類污染物(Mandaric et al., 2015)。在台灣，人們特別關注這個問題，因為台灣在 2020 年初通過了含有萊克多巴胺的美國牛肉進口。此外，由於疫情的爆發，許多學者致力於開發 covid-19 的藥物，然而奎寧是治療covid-19的藥物之一。不幸的是，這兩種化合物都是新興污染物。雖然這些污染物進入環境水體的濃度很低，但長時間暴露後會對生態系統產生不良影響。因此，本研究將實施高級氧化程序來降解目標化合物，透過芬頓降解程序與過硫酸鹽的高級氧化程序作為處理方式並同時比較兩種方法在處理目標污染物的處理效率，並在實驗同時改變催化劑，比較同相催化(硫酸亞鐵)與異相催化(四氧化三鐵)對於目標污染物移除比例的影響；此外，本實驗亦會加入石墨烯與腐植酸作為螯合劑，比較加入螯合劑對於整體反應機制的影響；最後，本研究以會將操作環境調整至中性環境，並模擬在中性偏酸的環境下，芬頓法與過硫酸鹽氧化法的操作可行性。此外，本研究將使用質譜儀來定義氧化程序實驗過程中的中間產物。並將結果輸入計算軟體中，計算生態結構活性關係，以確認降解反應可以解決環境中污染物的生物毒性。 在本研究結果顯示，同相催化與異相催化的比較中可以發現以亞鐵離子作為催化劑的同相催化效果明顯比四氧化三鐵好；加入螯合劑也可以增加整體的反應結果，尤其是在加入石墨烯作為螯合劑時，整體的反應速率與降解效果皆有顯著的提升；在酸性環境下，亞鐵離子更具活性，在中性環境時，亞鐵離子大多轉換為活性不高的鐵離子，因此整體降解效果不如酸性條件，然而，在四氧化三鐵催化實驗中改變pH值，整體結果差異不大，顯示在pH值偏中性或是波動較大的環境中，四氧化三鐵作為高級氧化程序的催化劑有更高的可行性；最後將兩種新興污染物的降解途徑和質譜結果輸入EPI Suite的軟體中，得到目標污染物降解的中間產物的生物毒性，可以發現污染物大多都被降解，整體生物毒性有所下降，因此可以推測芬頓法與過硫酸鹽氧化法在作為污染物降解程序為一種可行的方法。

Emerging pollutants are defined as chemical pollutants that “have not yet been identified or confirmed”, “are unregulated” and “pose a risk to human health and the environment” (Mandaric et al., 2015). This type of pollutant also cannot be effectively removed by the treatment units of existing sewage treatment plants and water purification plants. In Taiwan, people are particularly concerned about this issue because Taiwan passed U.S. beef, containing ractopamine, imports in early 2020. Moreover, due to the outbreak of the epidemic, many scholars have devoted themselves to developing medicines for covid-19. And quinine is one of the medicines for covid-19. Unfortunately, both of these compounds are emerging contaminants. Although the concentrations of these pollutants entering the environmental water body are very low, after a long period of exposure will have a bad impact on the ecosystem. Therefore, this study will implement an advanced oxidation procedure To degrade the target compound, the Fenton degradation process and the advanced oxidation process of persulfate were used as treatment methods and the treatment efficiency of the two methods in treating the target pollutants was compared at the same time, and the catalyst was changed in the experiment at the same time, and the homogeneous catalysis (ferrous sulfate) was compared. ) and heterogeneous catalysis (iron tetroxide) on the removal ratio of target pollutants; in addition, graphene and humic acid will be added as chelating agents in this experiment to compare the effect of adding chelating agents on the overall reaction mechanism; The study will adjust the operating environment to a neutral environment and simulate the operational feasibility of the Fenton method and the persulfate oxidation method in a neutral-to-acidic environment. In addition, this study will use a mass spectrometer to define the oxidation program experiment Intermediate products in the process. And input the results into the calculation software to calculate the ecological structure-activity relationship to confirm that the degradation reaction can solve the biological toxicity of pollutants in the environment. The results of this study showed that in the comparison of homogeneous catalysis and heterogeneous catalysis, it can be found that the homogeneous catalysis effect of ferrous ions as the catalyst is better than that of ferric ferrous oxide. Adding a chelating agent can also increase the overall reaction result, especially when adding graphene as a chelating agent, the overall reaction rate and degradation efficiency are significantly improved. In an acidic environment, ferrous ions are more active. While in a neutral environment, ferrous ions are mostly converted into less active iron ions. Therefore, the overall degradation effect is not as good as the acidic condition. However, in the ferric ferrous oxide catalysis experiment. Changing the pH value only caused little difference, showing that in the environment with a neutral pH value or a large fluctuation, the ferric ferrous oxide as a high-grade catalyst of the advanced oxidation procedure has higher feasibility. Finally, the degradation pathways and mass spectrometry results of the two emerging pollutants are input into the software of EPI Suite to obtain the biological toxicity, and it can be found that most of the pollutants are removed. Therefore, it can be speculated that the Fenton process and the sulfate radical-based advanced oxidation process are feasible methods in the degradation process of pollutants.