| 电化学氧化PFOA阳极材料筛选及其机制研究 |
| 摘要点击 2686 全文点击 1456 投稿时间：2013-09-13 修订日期：2013-12-02 |
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| 中文关键词 电化学 全氟辛酸 超声 BDD Ti/SnO2-Sb2O5 |
| 英文关键词 electrochemistry perfluorooctanoate(PFOA) ultrasonic BDD Ti/SnO2-Sb2O5 |
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| 中文摘要 |
| 全氟辛酸（PFOA）具有环境持久性及内分泌干扰性，传统的生物降解及高级氧化法对PFOA的去除效果微弱. 本研究采用电化学氧化法降解PFOA，选取BDD（掺硼金刚石电极）、Pt、Ti、Ti/RuO2、Ti/RuO2-IrO2、Ti/In2O3、Ti/SnO2-Sb2O5-IrO2、Ti/SnO2-Sb2O5-RhO2、Ti/SnO2-Sb2O5、Ti/SnO2-Sb2O5-CeO2和Ti/SnO2-Sb2O5-Bi2O3这11种阳极材料为备选电极. 采用线性扫描伏安法测试析氧电位（OEP），评价11种电极对PFOA的降解效果和脱氟效果，并采用超声-电化学协同方法间接证明PFOA分子在电极表面的直接电子转移是降解反应的第一步. Ti/SnO2-Sb2O5-Bi2O3、Ti/SnO2-Sb2O5-CeO2、Ti/SnO2-Sb2O5和BDD对PFOA有较好的电氧化效果，降解率分别是89.8%、89.8%、93.3%和98.0%. Pt、Ti/SnO2-Sb2O5-RhO2、Ti/SnO2-Sb2O5-IrO2和Ti/In2O3对PFOA的电氧化效果微弱，降解率分别是2.1%、2.3%、12.5%和3.1%. 而Ti、Ti/RuO2和Ti/RuO2-IrO2对PFOA没有电氧化能力. PFOA分子经过电极表面的直接电化学氧化发生脱羧反应，后经过逐步脱掉CF2单元的循环生成短链的全氟羧酸类化合物C6F13COO-、C5F11COO-、C4F9COO-和C3F7COO-. |
| 英文摘要 |
| Perfluorooctanoate (PFOA) is environmentally stable and endocrine-disrupting. It was resistant to conventional biodegradation and advanced oxidation processes. Electrochemical oxidation method was adopted to degrade PFOA. The anodes, including BDD, Pt, Ti, Ti/RuO2, Ti/RuO2-IrO2, Ti/In2O3, Ti/SnO2-Sb2O5-IrO2, Ti/SnO2-Sb2O5-RhO2, Ti/SnO2-Sb2O5, Ti/SnO2-Sb2O5-CeO2 and Ti/SnO2-Sb2O5-Bi2O3, were selected as the candidate materials. The oxygen evolution potential (OEP) were determined by linear sweep voltammetry (LSV). The degradation ratios and the defluorination ratios were used to evaluate the oxidation ability of anodic materials. Ultrasonic electrochemical oxidation indirectly demonstrated that direct electron transfer was the initial step for PFOA decomposition. The anodes of Ti/SnO2-Sb2O5-Bi2O3, Ti/SnO2-Sb2O5-CeO2, Ti/SnO2-Sb2O5 and BDD effectively degraded PFOA, and the decomposition ratios were 89.8%, 89.8%, 93.3% and 98.0%, respectively. The removal ratios of PFOA on Ti/SnO2-Sb2O5-RhO2, Ti/SnO2-Sb2O5-IrO2 and Ti/In2O3 anodes were low, and the values were 2.1%, 2.3%, 12.5% and 3.1%, respectively. However, Ti, Ti/RuO2 and Ti/RuO2-IrO2 had no effect on PFOA. PFOA molecule transferred electrons to the anode, decarboxylated, and followed the CF2 unzipping cycle. The intermediate products detected were C6F13COO-, C5F11COO-, C4F9COO- and C3F7COO-. |
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