Iodinated X-ray contrast media (ICM) compounds are a form of intravenous radiocontrast containing iodine, which are rapidly eliminated via urine or feces. The issue with the accumulation of ICM has received considerable critical attention since they are ubiquitously distributed in municipal wastewater effluents and in the aquatic environment and are not significantly eliminated by most biological sewage treatment processes. Among the methods that have been tested to eliminate ICM, electrochemical methods have significant advantages, since they can selectively cut the carbon-iodine bonds that are suspected to decrease their biodegradability. On the production sites, the recovery of iodine ions due to the carbon-iodine cleavage can be envisaged, which is particularly interesting to reduce the cost of the ICM production process. The coupling of an electrochemical process and a biological treatment can be carried out to mineralize the organic part of the formed by-products, allowing the recovery of the iodide ions. Therefore, the degradation of diatrizoate, a typical ionic ICM compound, by an electrochemical process was the purpose of this study. The electrochemical reduction of diatrizoate was performed using a flow cell with a graphite felt electrode at different potentials. The removal yield of diatrizoate reached ~100% in 2 h and the main product, 3,5-diacetamidobenzoic acid, was quantitatively formed, showing that diatrizoate was almost completely deiodinated. According to the BOD₅/COD ratio, the biodegradability of diatrizoate after electrolysis was considerably improved. Cyclic voltammetry analysis of the electroreduced solution showed several oxidation peaks. The electrochemical oxidation of the by-products formed after the first treatment by electroreduction was then performed at three different potentials to study the influence of electrochemical oxidation on biodegradability. Results showed that the degradation yield of the deiodinated by-products increased with the potential and reached 100% at 1.3 V/SCE. Four different biological treatments were implemented during 21 days in stirred flasks with fresh activated sludge. The evolution of the mineralization during the biological treatment highlighted the biorecalcitrance of diatrizoate as previously estimated by the BOD₅/COD ratio. Interestingly, the mineralization yield increased from 41 to 60% when electrochemical oxidation at 1.3 V/SCE was implemented after electroreduction.

碘化X射线造影剂（ICM）化合物是一种含碘的静脉放射造影剂，可通过尿液或粪便迅速清除。由于ICM的积累普遍存在于城市废水和水生环境中，并且大多数生物污水处理工艺并未将其消除，因此，ICM的积累问题已受到相当重要的关注。在已测试消除ICM的方法中，电化学方法具有显着优势，因为它们可以选择性地切断怀疑会降低其生物降解性的碳碘键。在生产现场，可以设想由于碳-碘裂解导致的碘离子的回收，这对于降低ICM生产过程的成本特别有意义。可以进行电化学过程和生物处理的结合以使形成的副产物的有机部分矿化，从而可以回收碘离子。因此，本研究的目的是通过电化学方法降解泛影酸盐（一种典型的离子型ICM化合物）。使用带有石墨毡电极的流通池在不同电势下进行泛影酸盐的电化学还原。在2小时内，泛影酸盐的去除率达到约100％，并且定量生成了主要产物3,5-二乙酰氨基苯甲酸，表明泛影几乎完全脱碘。根据董事会 本研究的目的是通过电化学方法降解泛影酸盐（一种典型的离子型ICM化合物）。使用带有石墨毡电极的流通池在不同电势下进行泛影酸盐的电化学还原。在2小时内，重氮酸盐的去除率达到〜100％，并且定量形成了主要产物3,5-二乙酰氨基苯甲酸，表明重氮酸盐几乎完全脱碘。根据董事会 本研究的目的是通过电化学方法降解泛影酸盐（一种典型的离子型ICM化合物）。使用带有石墨毡电极的流通池在不同电势下进行泛影酸盐的电化学还原。在2小时内，重氮酸盐的去除率达到〜100％，并且定量形成了主要产物3,5-二乙酰氨基苯甲酸，表明重氮酸盐几乎完全脱碘。根据董事会 说明泛氮几乎完全脱碘。根据董事会 表明泛氮几乎完全脱碘。根据董事会_在5 / COD比下，电解后泛影酸盐的生物降解性得到了显着改善。电解还原溶液的循环伏安分析显示了几个氧化峰。然后在三种不同的电势下对经过电还原的第一处理后形成的副产物进行电化学氧化，以研究电化学氧化对生物降解能力的影响。结果表明，脱碘副产物的降解产率随着电势的增加而增加，在1.3 V / SCE时达到100％。在21天内用新鲜的活性污泥在搅拌的烧瓶中进行了四种不同的生物处理。生物处理过程中矿化的演变突显出BOD ₅先前估计的泛影酸盐的生物抵抗性。/ COD比。有趣的是，在电还原后以1.3 V / SCE进行电化学氧化时，矿化产率从41％增加到60％。