de Melo Costa-Serge Nayara, Gonçalves Rosembergue Gabriel Lima, Rojas-Mantilla Hernán Dario, Santilli Celso Valentim, Hammer Peter, Nogueira Raquel Fernandes Pupo
São Paulo State University (UNESP), Institute of Chemistry, 14800-900 Araraquara, SP, Brazil; UNESP, National Institute for Alternative Technologies of Detection, Toxicological Evaluation and Removal of Micropollutants and Radioactives (INCT - DATREM), Institute of Chemistry, 14800-060 Araraquara, SP, Brazil.
São Paulo State University (UNESP), Institute of Chemistry, 14800-900 Araraquara, SP, Brazil.
J Hazard Mater. 2021 Jul 5;413:125388. doi: 10.1016/j.jhazmat.2021.125388. Epub 2021 Feb 12.
The catalytic activity of layered double hydroxides, with and without insertion of copper, was evaluated in a heterogeneous Fenton process for degradation of the antibiotic sulfathiazole (STZ). The characterizations with different techniques revealed lamellar structures formed by stacking of layers containing magnesium, iron, and copper cations. The insertion of copper in the lamellar structure increased the specific area of the material and the degradation kinetics, achieving complete STZ removal after 90 min. X-ray photoelectron spectroscopy analysis showed the presence of Cu(II) and Cu(I) surface sites, which contributed to the generation of hydroxyl and hydroperoxyl/superoxide radicals. It also indicated an increase of Cu(I) content after use. For both materials, but specially for LDH without copper, addition of tert-butyl alcohol and p-benzoquinone hindered STZ degradation, indicating the importance of hydroxyl and hydroperoxyl/superoxide radicals in the degradation process, respectively. These results demonstrated the potential of copper-modified MgFe-CO as a catalyst for the degradation of emerging contaminants, offering the benefits of easy preparation and high efficiency in the Fenton process.
在非均相芬顿过程中，评估了有无铜插入的层状双氢氧化物对抗生素磺胺噻唑（STZ）的催化降解活性。不同技术表征显示，其层状结构由含镁、铁和铜阳离子的层堆叠而成。铜插入层状结构增加了材料的比表面积和降解动力学，90分钟后实现了STZ的完全去除。X射线光电子能谱分析表明存在Cu(II)和Cu(I)表面位点，这有助于羟基和氢过氧根/超氧根自由基的产生。使用后还表明Cu(I)含量增加。对于这两种材料，特别是不含铜的层状双氢氧化物，加入叔丁醇和对苯醌会阻碍STZ降解，分别表明羟基和氢过氧根/超氧根自由基在降解过程中的重要性。这些结果证明了铜改性的MgFe-CO作为新兴污染物降解催化剂的潜力，在芬顿过程中具有易于制备和高效的优点。
