School of Environmental Science and Engineering, Huazhong University of Science and Technology, Wuhan, 430074, China; Hubei Key Laboratory of Multi-Media Pollution Cooperative Control in Yangtze Basin, School of Environmental Science and Engineering, Huazhong University of Science and Technology, Wuhan, 430074, China.
School of Chemical Sciences, Universiti Sains Malaysia, Penang, 11800, Malaysia.
Chemosphere. 2024 Aug;362:142635. doi: 10.1016/j.chemosphere.2024.142635. Epub 2024 Jun 17.
Electrochemical advanced oxidation processes (EAOPs) based on natural air diffusion electrode (NADE) promise efficient and affordable advanced oxidation water purification, but the sustainable operation of such reaction systems remains challenging due to severe cathode electrowetting. Herein, a novel floating cathode (FC) composed of a stable hydrophobic three-phase interface was established by designing a flexible catalytic layer of FC. This innovative electrode configuration could effectively prolong the service life of the cathode by mitigating the interference of H bubbles from the hydrogen evolution reaction (HER), and the HO production rate reached 37.59 mg h·cm and realize a long-term stable operation for 10 h. Additionally, an FC/carbon felt (CF) dual-cathode electro-Fenton system was constructed for in situ sulfamethoxazole (SMX) degradation. Efficient HO production on FC and Fe(III) reduction on CF were synchronously achieved, attaining excellent degradation efficiency for both SMX (ca. 100%) with 2.5 mg L of Fe(Ⅱ) injection. For real wastewater, the COD removal of the FC/CF dual-cathode electro-Fenton system was stabilized at exceeding 75%. The practical application potential of the FC/CF dual-cathode electro-Fenton system was also demonstrated for the treatment of actual landfill leachate in continuous flow mode. This work provides a valuable path for constructing a sustainable dual-cathode electro-Fenton system for actual wastewater treatment.
基于自然空气扩散电极（NADE）的电化学高级氧化工艺（EAOPs）有望实现高效且经济实惠的高级氧化水净化，但由于阴极严重的电润湿现象，此类反应系统的可持续运行仍然具有挑战性。在此，通过设计 FC 的柔性催化层，建立了由稳定的疏水三相界面组成的新型浮动阴极（FC）。这种创新的电极结构可以有效地通过减轻来自析氢反应（HER）的 H 气泡的干扰来延长阴极的使用寿命，HO 生成速率达到 37.59mg h·cm，并实现了长达 10 小时的长期稳定运行。此外，构建了 FC/碳纤维毡（CF）双阴极电芬顿体系，用于原位磺胺甲恶唑（SMX）降解。FC 上高效的 HO 生成和 CF 上的 Fe(III)还原同时实现，在注入 2.5mg L Fe(Ⅱ)时，SMX 的降解效率达到近 100%。对于实际废水，FC/CF 双阴极电芬顿系统的 COD 去除率稳定在 75%以上。还通过连续流动模式展示了 FC/CF 双阴极电芬顿系统用于实际垃圾渗滤液处理的实际应用潜力。这项工作为构建用于实际废水处理的可持续双阴极电芬顿系统提供了一条有价值的途径。
