Electro-assisted activation of peroxymonosulfate in the presence of chloride ion for degradation of sulfamethoxazole

• Published in: Journal of cleaner production 2023-06, Vol.405, p.136914, Article 136914
• Main Authors: Bu, Jiaqi, Jiang, Hongru, Li, Tianhao, Zhou, Chengyun, Zhong, Shian
• Format: Article
• Language: English
• Subjects: chlorides; chlorine; Chlorine evolution effect; computer software; Coriolus versicolor; Electric-field activation; electrochemistry; electrodes; liquid chromatography; mass spectrometry; oxygen; Peroxymonosulfate; polysaccharides; Sulfamethoxazole; TiO2/RuO2–IrO2 electrode; toxicity; wastewater; water quality
• ISSN: 0959-6526; 1879-1786
• DOI: 10.1016/j.jclepro.2023.136914

A laboratory-scale electrochemical reaction tank was self-designed for the degradation of sulfamethoxazole (SMZ). Coupling electrocatalysis (EC) with personoxysulfate (PMS) and chloride ion (Cl−), the degradation system of EC + PMS + Cl was established. The degradation efficiency of the EC + PMS + Cl system for SMZ (10 mg/L) reached 100% within 20 min, and the degradation process of SMZ conforms to the first-order kinetics. EC + PMS + Cl system also has good degradation efficiency for other organic pollutants or polysaccharide wastewater (real wastewater) from coriolus versicolor. The electrochemical performance test shows that TiO2/RuO2–IrO2 electrode not only has a good chlorine evolution effect but also has good stability. •OH and active chlorine play a major role in the degradation system. Theoretical calculation (DFT) and XPS analyses confirm that the RuO2–IrO2 site as an active center activates PMS and Cl− into active oxygen and active chlorine, and the TiO2 site as an active center activates molecular oxygen into active oxygen. The results of liquid chromatography and mass spectrometry (LC-MS) and Toxicity Estimation Software Tool (TEST) showed that the water quality of SMZ after 20 min of degradation was almost harmless. Therefore, this research work will provide a new vision for the electrocatalytic degradation of organic wastewater. [Display omitted] •EC + PMS + Cl system exhibits outstanding degradation efficiency for sulfamethoxazole (SMZ).•RuO2–IrO2 has good chlorine evolution under the action of the electric field.•OH and active chlorine play a major role in the degradation system.•The degradation efficiency for SMZ was less affected by complex water conditions.•The water quality of SMZ after 20 min of degradation was almost harmless.