Detection of Oxidants Such as Hydroxyl Radicals and Chlorine Electrogenerated on a BDD Electrode by Simple Methods  

作　　者：Konan Sylvestre Koffi Konan Martin Koffi Foffié Thiery Auguste Appia Sahi Placide Sadia Kouakou Jocelin Kimou Souleymane Kone Lassiné Ouattara Konan Sylvestre Koffi;Konan Martin Koffi;Foffié Thiery Auguste Appia;Sahi Placide Sadia;Kouakou Jocelin Kimou;Souleymane Kone;Lassiné Ouattara(Laboratoire de Constitution et de Raction de la Matire, UFR SSMT, Universit Flix Houphout Boiguy, Abidjan, Cte dIvoire;UFR Environnement, Universit Jean Lorougnon Gud, Daloa, Cte dIvoire)

机构地区：[1]Laboratoire de Constitution et de Raction de la Matire, UFR SSMT, Universit Flix Houphout Boiguy, Abidjan, Cte dIvoire [2]UFR Environnement, Universit Jean Lorougnon Gud, Daloa, Cte dIvoire

出　　处：《Advances in Chemical Engineering and Science》2024年第4期173-187,共15页化学工程与科学期刊（英文）

摘　　要：The aim of this work is to detect electrogenerated hydroxyl radicals and chlorine by simple and less expensive methods. Preparative electrolyses of perchloric acid (HClO4) and sodium chloride (NaCl) were performed on a boron-doped diamond (BDD) electrode. The hydroxyl radicals were quantified indirectly by assaying the samples from the HClO4 (0.1 M) electrolysis with a 10−4 M potassium permanganate solution. The investigations showed that the amount of hydroxyl radicals depends on the concentration of HClO4 and the current density. As for chlorine, a qualitative determination was carried out. A mixture of the electrolyte solution of HClO4 (0.1 M) + NaI (0.2 M) + 2 mL of hexane, taken in this order, leads to a purplish-pink coloration attesting to the presence of Cl2. The same test was carried out with NaBr and NaI giving pale and very pale pink colourations, respectively, showing that the intensity of the colouration depends on the strength of the oxidant present. In addition, oxidants were detected during the electrooxidation of metronidazole (MNZ). The results showed the participation of electrogenerated hydroxyl radicals. The generation of chlorine has also been proven. Furthermore, the degradation leads to a chemical oxygen demand (COD) removal rate of 83.48% and the process is diffusion-controlled.The aim of this work is to detect electrogenerated hydroxyl radicals and chlorine by simple and less expensive methods. Preparative electrolyses of perchloric acid (HClO4) and sodium chloride (NaCl) were performed on a boron-doped diamond (BDD) electrode. The hydroxyl radicals were quantified indirectly by assaying the samples from the HClO4 (0.1 M) electrolysis with a 10−4 M potassium permanganate solution. The investigations showed that the amount of hydroxyl radicals depends on the concentration of HClO4 and the current density. As for chlorine, a qualitative determination was carried out. A mixture of the electrolyte solution of HClO4 (0.1 M) + NaI (0.2 M) + 2 mL of hexane, taken in this order, leads to a purplish-pink coloration attesting to the presence of Cl2. The same test was carried out with NaBr and NaI giving pale and very pale pink colourations, respectively, showing that the intensity of the colouration depends on the strength of the oxidant present. In addition, oxidants were detected during the electrooxidation of metronidazole (MNZ). The results showed the participation of electrogenerated hydroxyl radicals. The generation of chlorine has also been proven. Furthermore, the degradation leads to a chemical oxygen demand (COD) removal rate of 83.48% and the process is diffusion-controlled.

关 键 词：ELECTROOXIDATION Hydroxyl Radicals CHLORINE DETECTION 

分 类 号：O62[理学—有机化学]