Motta, Fabiana Villela daOliveira, Patrícia Merlim de2019-05-142021-09-292019-05-142021-09-292019-05-02OLIVEIRA, Patrícia Merlim de. Influência do pH na morfologia do CuO obtido via método sonoquímico utilizando diferentes surfactantes. 2019. 66 f. Trabalho de Conclusão de Curso (Graduação em Engenharia de Materiais) - Centro de Tecnologia, Departamento de Engenharia de Materiais, Universidade Federal do Rio Grande do Norte, Natal, 2019.https://repositorio.ufrn.br/handle/123456789/40352The textile industry is considered one of the largest water wasters in the world and the waste generated in the process represents a worrying threat to the ecosystem due to the organic pollutants been difficult to treat by regular methods. Advanced oxidation processes (AOPs) have been considered a sustainable and efficient technique for the treatment of textile wastewater, in which highly reactive hydroxyl radicals •OH are produced and generating the dye oxidative degradation process, generally, using a solid semiconductor as a catalyst. Alterations in the conventional semiconductors properties were studied in order to be optimized. In this work, copper oxide II (CuO) powders were synthesized via a sonochemical using different surfactants (PVP, PEG, and EDA), varying synthesis pH at 8, 11 and 13. The powders were characterized by X-ray diffraction (XRD), field emission scanning electron microscopy (SEM), Brunauer-Emmett-Teller method (BET), UV–Visible spectroscopy (UV–Vis) and Fourier transform infrared spectroscopy (FTIR). Photocatalytic tests were performed to evaluate the applicability of CuO powders in the degradation of the methylene blue dye. XRD patterns showed that a pH increase from 8 to 13 favors CuO single phase formation, whereas Cu2(OH)3(NO3) secondary peaks appear at lower pH values (8 and 11). FTIR spectra confirmed the appearance of Cu2(OH)3(NO3) through nitrate hydroxide related vibration. The SEM images showed the variations in morphology obtained through the different surfactants and the medium pH, in which, the morphology presents a leaf appearance with a lower value (pH = 8), while increasing the pH to 13, changed the morphology into agglomerate flower-like nanoparticles. The BET results showed that the samples obtained without surfactant and with PEG at pH = 8 had the highest and lowest surface area, being 18,935 and 4,531 m2.g-1, respectively. Photocatalytic tests indicated that the increase in surface area favors photocatalytic activity, where the sample without surfactant obtained at pH 8 and the sample obtained with PVP at pH 11 reduced the concentration of the methylene blue dye by 100%.Attribution-NonCommercial-NoDerivs 3.0 Brazilhttp://creativecommons.org/licenses/by-nc-nd/3.0/br/Método sonoquímicoAlteração morfológicaFotocatáliseCuOCu2(OH)3(NO3)Sonochemical methodMorphological alterationPhotocatalysisbachelorThesis