Traditional reduction or oxidation processes generating one−component free radicals face challenges in deep dechlorination and mineralization of chlorophenols from wastewater. Herein, an efficient electrocatalytic process has been developed, which couples atomic H* reduction with reactive oxidation species (OH and O) oxidation on a bifunctional cathode for 4 −chlorophenol (4 −CP) removal. The N − doped carbon nanotubes encapsulated manganese nanoparticles was fabricated as cathode, which could generate atomic H* , initiating nucleophilic hydrodechlorination in presence of confined MnO sites. Subsequently, electrophilic oxidation by generating mainly O on confined MnC sites and OH on confined MnO sites, facilitating the oxidative processes. Experimental results and theory calculations demonstrated that reductive dechlorination and oxidative mineralization processes could mutually promote each other, resulting in an enhancement factor of 2.90. At pH 7, this process achieved 100 % removal for 4 −CP, 84 % dechlorination, 76 % total organic carbon (TOC) removal and low energy consumption (0.76 kWh g) within 120 min. Notably, TOC for chlorophenols containing Cl substituents at different positions and real lake water containing 4 −CP could be almost completely removed. This research establishes confined non−noble bifunctional active sites that synergistically enhance reductive dechlorination and oxidative degradation processes, holding significant treatment potential for application in deep mineralization of organochlorine from water/wastewater.

中文翻译：

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限制锰双功能位点上原子氢还原和活性氧氧化的协同作用用于电催化深层矿化


产生单组分自由基的传统还原或氧化过程在废水中氯酚的深度脱氯和矿化方面面临挑战。在此，开发了一种高效的电催化工艺，该工艺将原子 H* 还原与双功能阴极上的活性氧化物质（OH 和 O）氧化结合起来，以去除 4 - 氯酚 (4 -CP)。将N-掺杂碳纳米管封装的锰纳米粒子制成阴极，它可以产生原子H*，在有限的MnO位点存在下引发亲核加氢脱氯。随后，通过在受限的 MnC 位点上主要生成 O 和在受限的 MnO 位点上生成 OH 来进行亲电氧化，从而促进氧化过程。实验结果和理论计算表明，还原脱氯和氧化矿化过程可以相互促进，增强因子达到2.90。在 pH 7 时，该工艺在 120 分钟内实现了 4 −CP 100% 去除、脱氯 84%、总有机碳 (TOC) 去除 76% 以及低能耗（0.76 kWh g）。值得注意的是，在不同位置含有 Cl 取代基的氯酚和含有 4 -CP 的真实湖水的 TOC 几乎可以完全去除。这项研究建立了有限的非贵重双功能活性位点，可协同增强还原脱氯和氧化降解过程，在水/废水中有机氯的深度矿化应用中具有巨大的处理潜力。