Evaluation of in situ water electrochemical disinfection using novel carbon-based and noble metal electrodes

• Published in: Euro-Mediterranean journal for environmental integration 2018-11, Vol.3 (1), p.31, Article 31
• Main Authors: Guizani, Mokhtar, Yajima, Kento, Kawaguchi, Toshikazu, Ito, Ryusei, Funamizu, Naoyuki
• Format: Article
• Language: English
• Subjects: Alloys; Aquatic Pollution; Atmospheric Protection/Air Quality Control/Air Pollution; Carbon; Catalytic activity; Chemical composition; Chemicals; Chloride; Chlorine; Disinfection; Earth and Environmental Science; Earth Sciences; Efficiency; Electrochemistry; Electrodes; Electron states; Electrons; Environmental Chemistry; Environmental Management; Environmental Science and Engineering; Fuel cells; Gold; Gold base alloys; Graphene; Hazardous materials; Heavy metals; Iodine; Metals; Morphology; Noble metals; Original Paper; Oxidation; Palladium; Phenylenediamine; Photoelectron spectroscopy; Photoelectrons; Scanning electron microscopy; Stability; Surface water; Titanium; Titanium dioxide; Waste Management/Waste Technology; Waste Water Technology; Water Management; Water Pollution Control; X ray photoelectron spectroscopy
• ISSN: 2365-6433; 2365-7448
• DOI: 10.1007/s41207-018-0075-8

In this study, the morphology, chemical composition, and electrochemical characteristics of three carbon-based and three noble metal/alloy electrodes were evaluated. Measurement of free chlorine production was carried out using iodine–starch method. Measurement of hypochlorite production was performed using N , N -diethyl- p -phenylenediamine (DPD). The electro-catalytic activity of the electrodes was characterized using cyclic voltammetry (CV). Among the noble metals, the gold–palladium alloy electrode showed the best catalytic performance. Among the carbon-based electrodes, TiC showed the best catalytic performance. Scanning electron microscopy (SEM) images before and after reaction confirms the stability of the TiC electrode, proving its potential for long-term use. The chemical structure of the electrodes was characterized using X-ray photoelectron spectroscopy (XPS) and this showed that carbon electrodes present a trace graphene oxide structure (sp 3 orbitals C–OH/C–O). Moreover, the modification of porous carbon by vacuum-assisted TiO 2 impregnation indicates that the electronic state of TiC did not change due to impregnation with TiO 2 . In summary, the TiC carbon-based electrode shows high stability and potential for long use.