Grupo de Investigación en Remediación Ambiental y Biocatálisis (GIRAB), Instituto de Química, Facultad de Ciencias Exactas y Naturales, Universidad de Antioquia UdeA, Calle 70 No. 52-21, Medellín, Colombia.
Research Institute for Pesticides and Water (IUPA), University Jaume I (UJI), Castellón, Spain.
Water Res. 2019 May 1;154:349-360. doi: 10.1016/j.watres.2019.01.045. Epub 2019 Feb 5.
The simultaneous degradation of seventeen emerging concern pollutants in effluent from the municipal wastewater treatment plant (MWTP) of Bogotá-Colombia was studied using high frequency ultrasound (375 kHz). The considered compounds in the effluent corresponded to pharmaceuticals (diclofenac, carbamazepine, venlafaxine, ciprofloxacin, norfloxacin, valsartan, losartan, irbesartan, sulfamethoxazole, clarithromycin, azithromycin, erythromycin, metronidazole, trimethoprim and clindamycin); cocaine and its major metabolite benzoylecgonine. Due to limitation of the MWTP for the pollutants elimination, ultrasound was applied to remove these compounds. Interestingly, ultrasonic physical action led to releasing of ciprofloxacin, norfloxacin, diclofenac and sulfamethoxazole from suspended solids, whereas the chemical effects induced degradation of the rest of compounds. For the latter ones, an interesting correlation between the sonodegradation and arithmetic multiplication between hydrophobicity and concentration of pollutants was established. Afterwards, the sonochemical process was complemented with ferrous ions (sono-Fenton), ferrous ions plus light (sono-photo-Fenton) or ferrous ions plus light in presence of oxalic acid (sono-photo-Fenton/oxalic acid). Additionally, to clarify fundamental aspects of the different systems, individual treatments in distilled water of a model pollutant (valsartan) were performed. The complemented processes significantly enhanced all compounds degradation, following the order: sono-photo-Fenton/oxalic acid > sono-photo-Fenton ∼ sono-Fenton > sonochemistry. The Fe addition improved the pollutants elimination by generation of more hydroxyl radicals in the solution bulk. Meanwhile, oxalic acid avoided Fe precipitation favoring the iron catalytic cycle. Thus, the work demonstrates the high potentiality of the sono-photo-Fenton/oxalic acid system for the pollutants elimination in real-world wastewater matrices.
采用高频超声（375kHz）研究了哥伦比亚波哥大市污水处理厂（MWTP）出水中 17 种新兴关注污染物的同时降解。废水中考虑的化合物为药物（双氯芬酸、卡马西平、文拉法辛、环丙沙星、诺氟沙星、缬沙坦、氯沙坦、厄贝沙坦、磺胺甲恶唑、克拉霉素、阿奇霉素、红霉素、甲硝唑、甲氧苄啶和克林霉素）；可卡因及其主要代谢物苯甲酰爱康宁。由于 MWTP 对污染物的消除有限，因此应用超声去除这些化合物。有趣的是，超声物理作用导致悬浮固体中释放出环丙沙星、诺氟沙星、双氯芬酸和磺胺甲恶唑，而其余化合物则是通过化学作用降解的。对于后者，建立了超声降解与污染物疏水性和浓度的算术乘法之间的有趣相关性。随后，在亚铁离子（超声-Fenton）、亚铁离子加光（超声-光-Fenton）或亚铁离子加光存在下补充草酸（超声-光-Fenton/草酸）的声化学过程。此外，为了阐明不同体系的基本方面，在去离子水中对模型污染物（缬沙坦）进行了单独处理。补充处理显著提高了所有化合物的降解，其顺序为：超声-光-Fenton/草酸>超声-光-Fenton≈超声-Fenton>声化学。铁的加入通过在溶液本体中生成更多的羟基自由基来提高污染物的去除效率。同时，草酸避免了铁的沉淀，有利于铁的催化循环。因此，这项工作证明了超声-光-Fenton/草酸体系在实际废水基质中去除污染物的高潜力。
