Department of Chemical Engineering, School of Industrial Engineering, University of Castilla-La Mancha, 02071, Albacete, Spain.
Department of Chemical Engineering, Faculty of Chemical Sciences and Technologies, University of Castilla-La Mancha, 13005, Ciudad Real, Spain.
Water Res. 2018 Jan 1;128:383-392. doi: 10.1016/j.watres.2017.10.072. Epub 2017 Nov 1.
Hospital effluents are a major source for the occurrence of pharmaceuticals in the environment. In this work, the treatment of synthetic urine polluted with chloramphenicol is studied by using three different conductive-diamond electrochemical oxidation technologies: electrolysis (single electrolysis), photoelectrolysis and high-frequency ultrasound sonoelectrolysis. These technologies were evaluated at 10 and 100 mA cm. Results shows that not only chloramphenicol but also other organics contained in urine are completely mineralized by electrolysis. Ammonium is the main inorganic nitrogen species formed and it can react with the electrogenerated hypochlorite, favouring the formation of chloramines. These species prevent the potential formation of perchlorate from chlorides contained in urine at low current densities (10 mA cm) and delay its occurrence at high current densities (100 mA cm). On the other hand, irradiation of ultraviolet (UV) light or high-frequency ultrasound (US) produce changes in the performance of the electrolytic treatment, but these changes are not as important as in other cases of study shown in the literature. Nonetheless, the effect of electroirradiated technologies seems to be higher and depends on the type of pollutant when working at low current densities (10 mA cm). It is positive in the case of the degradation of the antibiotic and the uric acid and negative in the case of urea where there is a clear antagonistic effect. Production of oxidants increases with the current density although in lower ratio than expected. These results are of great importance because clearly point out that electrolytic technologies can be applied to minimize the diffuse pollution associated to pharmaceuticals before discharge into municipal sewers.
医院废水是环境中药物出现的主要来源。在这项工作中，使用三种不同的导电金刚石电化学氧化技术（电解、光电解和高频超声协同电解）来处理受氯霉素污染的合成尿液。这些技术在 10 和 100 mA cm 下进行了评估。结果表明，不仅氯霉素，而且尿液中所含的其他有机物都通过电解完全矿化。形成的主要无机氮物种是铵，它可以与电生成的次氯酸盐反应，有利于氯胺的形成。这些物质在低电流密度（10 mA cm）下防止了尿液中所含的氯化物形成高氯酸盐，而在高电流密度（100 mA cm）下延迟了其形成。另一方面，紫外线（UV）光或高频超声（US）的照射会改变电解处理的性能，但这些变化不如文献中其他情况下的研究那么重要。尽管如此，电辐照技术的效果似乎更高，并且取决于低电流密度（10 mA cm）下工作时的污染物类型。在抗生素和尿酸的降解方面是积极的，而在尿素方面则是消极的，因为存在明显的拮抗作用。尽管氧化剂的产生比例低于预期，但随着电流密度的增加而增加。这些结果非常重要，因为它们清楚地指出，电解技术可用于在排入城市污水之前，最大限度地减少与药物相关的扩散污染。
