Tianjin Key Laboratory of Chemical Process Safety, Hebei Collaborative Innovation Center of Modern Marine Chemical Technology, Engineering Research Center of Seawater Utilization of Ministry of Education, School of Chemical Engineering and Technology, Hebei University of Technology, Tianjin 300130, China.
Department of Chemical and Biochemical Engineering, Western University, London, ON N6A 5B9, Canada.
Molecules. 2023 Jun 9;28(12):4666. doi: 10.3390/molecules28124666.
Electrochemical reduction of nitrate has broad application prospects. However, in traditional electrochemical reduction of nitrate, the low value of oxygen produced by the anodic oxygen evolution reaction and the high overpotential limit its application. Seeking a more valuable and faster anodic reaction to form a cathode-anode integrated system with nitrate reaction can effectively accelerate the reaction rate of the cathode and anode, and improve the utilization of electrical energy. Sulfite, as a pollutant after wet desulfurization, has faster reaction kinetics in its oxidation reaction compared to the oxygen evolution reaction. Therefore, this study proposes an integrated cathodic nitrate reduction and anodic sulfite oxidation system. The effect of operating parameters (cathode potential, initial NO-N concentration, and initial SO-S concentration) on the integrated system was studied. Under the optimal operating parameters, the nitrate reduction rate in the integrated system reached 93.26% within 1 h, and the sulfite oxidation rate reached 94.64%. Compared with the nitrate reduction rate (91.26%) and sulfite oxidation rate (53.33%) in the separate system, the integrated system had a significant synergistic effect. This work provides a reference for solving nitrate and sulfite pollution, and promotes the application and development of electrochemical cathode-anode integrated technology.
电化学还原硝酸盐具有广阔的应用前景。然而，在传统的硝酸盐电化学还原中，阳极析氧反应产生的氧气价值低和过电位高限制了其应用。寻求更有价值和更快的阳极反应，形成与硝酸盐反应的阴极-阳极集成系统，可以有效地加速阴极和阳极的反应速率，提高电能的利用率。亚硫酸盐作为湿式脱硫后的污染物，其氧化反应的动力学比析氧反应更快。因此，本研究提出了一种集成的阴极硝酸盐还原和阳极亚硫酸盐氧化系统。研究了操作参数（阴极电位、初始 NO-N 浓度和初始 SO-S 浓度）对集成系统的影响。在最佳操作参数下，集成系统在 1 小时内达到 93.26%的硝酸盐还原率，亚硫酸盐氧化率达到 94.64%。与单独系统中的硝酸盐还原率（91.26%）和亚硫酸盐氧化率（53.33%）相比，集成系统具有显著的协同效应。这项工作为解决硝酸盐和亚硫酸盐污染提供了参考，并促进了电化学阴极-阳极集成技术的应用和发展。
