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年度	108	專案性質	實驗性質
專案類別	研究專案	研究主題	整治
申請機構	國立台灣大學	申請系所	環境工程學研究所
專案主持人	林逸彬	職等/職稱	副教授
專案中文名稱	以活化還原方式降解地下水中全氟辛酸及全氟辛烷磺酸之研究
中文關鍵字	活化還原, 全氟辛酸,全氟辛烷磺酸
專案英文名稱	Degradation of perfluorooctanoic acid and perfluorooctanesulfonic acid in groundwater by activated reduction
英文關鍵字	Peroxydisulfate; H2O2; superoxide radical; PFOA; PFOS
執行金額	1,097,438元
執行期間	2019/1/1 至 2019/11/30
計畫中文摘要	全氟辛酸及全氟辛烷磺酸，為含氟之長碳鏈有機化合物，因其化學結構特性具有較佳之熱穩定性、抗氧化能力，且難以在傳統的水處理程序中達到有效的處理。由於長期暴露可能對人體健康造成危害，全球許多國家或環境組織已針對此類含氟化學物質進行限制或禁止其使用，在台灣也已經將全氟辛酸及全氟辛烷磺酸列管為毒性化學物質。因氟元素本身有較大的電負度，代表其具有較好的吸引電子能力，使用氧化方式對含氟有機物質進行處理的效果並不顯著。由於目標污染物的化學特性，本研究使用活化還原方式，預期以二氧化錳活化過氧化氫 (MnO2/H2O2)產生之活性物質，在不同的水質參數條件下，以批次式反應分別評估不同活化處理方式對全氟辛酸及全氟辛烷磺酸降解的能力。 研究結果顯示在MnO2/H2O2活化還原反應系統中， PFOA及PFOS可以在此系統於7分鐘內降解45 % PFOA及80% PFOS。在高濃度H2O2 ( > 1M)、低目標污染物濃度有較佳之去除效率，且系統之初始pH介於5-9間不影響降解效率。目標污染物的降解在含有氯離子、碳酸氫根離子、天然有機物或真實地下水環境的條件下影響不大，但須考量系統H2O2濃度隨時間存在的問題，選擇適當的MnO2劑量。綜合自由基捕捉劑實驗及電子順磁共振分析結果，推論參與反應的自由基可能包含氫氧自由基與超氧自由基。
計畫英文摘要	Perfluorooctanoic acid (PFOA) and perfluorooctanesulfonic acid (PFOS) are long-chain fluorinated organic compounds possessing excellent thermal stability and oxidative resistance. They are stable in the environment and difficult to be degraded using traditional water treatment processes. Their applications have been restricted or prohibited in many countries considering their potential harm to human health after long-term exposure. In Taiwan, PFOA and PFOS have been regulated as toxic chemicals. Advanced oxidation processes have been shown ineffective for their removal. Considering the high electronegativity of fluorine in the PFOA and PFOS structures, reductive degradation would be more suitable for their removal. In this project, activated reduction process (MnO2/H2O2) was conducted on the reductive degradation for PFOA and PFOS. Our results show that PFOA and PFOS could be degraded in the MnO2/H2O2 activated reduction process, in which 45% and 80% removal can be achieved in 7 minutes for PFOA and PFOS, respectively. A high H2O2 concentration ( > 1 M) and a low target pollutant concentration were found to have a better performance in the system. No obvious inhibition of target pollutant degradation was found in the initial pH range of 5 to 9 or in the presence of Cl-, HCO3- and humid acid. This activated reduction process can be applied in real groundwater matrix. Based on the results of quenching experiments and electron paramagnetic resonance (EPR) analysis, it is concluded that hydroxyl radical and superoxide radical could be involved in the degradation of PFOA and PFOS.