Liu Yanbiao, Mei Jiancheng, Shen Chensi, Huang Manhong, Yang Ming, Wang Zhiwei, Sand Wolfgang, Li Fang
Textile Pollution Controlling Engineering Center of Ministry of Environmental Protection, College of Environmental Science and Engineering, Donghua University 2999 North Renmin Road Shanghai 201620 P. R. China
Shanghai Institute of Pollution Control and Ecological Security 1239 Siping Road Shanghai 200092 P. R. China.
RSC Adv. 2020 Jan 8;10(3):1219-1225. doi: 10.1039/c9ra07470h. eCollection 2020 Jan 7.
In this study, we have developed a continuous-flow electrochemical system towards the rapid and selective conversion of ammonia to N, based on a tubular substoichiometric titanium dioxide (TiO) anode and a Pd-Cu co-modified Ni foam (Pd-Cu/NF) cathode, both of which are indispensable. Under the action of a suitable anode potential, the TiO anode enables the conversion of Cl to chloride radicals (Cl˙), which could selectively react with ammonia to produce N. The anodic byproducts, NO , were further reduced to N at the Pd-Cu/NF cathode. EPR and scavenger experiments confirmed the dominant role of Cl˙ in ammonia conversion. Complete transformation of 30 mg L ammonia could be obtained over 40 min of continuous operation under optimal conditions. The proposed electrochemical system also exhibits enhanced oxidation kinetics compared to conventional batch systems. This study provides new insights into the rational design of a high-performance electrochemical system to address the challenging issue of ammonia pollution.
在本研究中，我们基于管状亚化学计量二氧化钛（TiO₂）阳极和钯 - 铜共修饰泡沫镍（Pd - Cu/NF）阴极，开发了一种用于将氨快速选择性转化为氮气的连续流电化学系统，这两者都是不可或缺的。在合适的阳极电位作用下，TiO₂阳极能使Cl⁻转化为氯自由基（Cl˙），其可与氨选择性反应生成氮气。阳极副产物NOₓ在Pd - Cu/NF阴极进一步还原为氮气。电子顺磁共振（EPR）和清除剂实验证实了Cl˙在氨转化中的主导作用。在最佳条件下连续运行40分钟，可实现30 mg L⁻¹氨的完全转化。与传统间歇系统相比，所提出的电化学系统还表现出增强的氧化动力学。本研究为合理设计高性能电化学系统以解决氨污染这一具有挑战性的问题提供了新的见解。
