Engenharia de Materiais (UACSA)
URI permanente desta comunidadehttps://arandu.ufrpe.br/handle/123456789/2913
Siglas das Coleções:
APP - Artigo Publicado em Periódico
TAE - Trabalho Apresentado em Evento
TCC - Trabalho de Conclusão de Curso
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3 resultados
Resultados da Pesquisa
Item Síntese e caracterização de um material nanoestruturado magnético, para adsorção de resíduos de corantes em meio líquido(2022-10-06) Alencar, Ellen Oliveira de Assis; Araújo, Ana Cláudia Vaz de; http://lattes.cnpq.br/6861890992609511; http://lattes.cnpq.br/0326211164564344Pernambuco's agreste region has developed with the growth of the local textile industry, this growth has brought with it the pollution of some rivers in the region. One of the steps in the fabric manufacturing process is dyeing, which uses synthetic dyes with high stability and resistance to degradation. In the fabric washing process, excess dye is released from the fibers and generates contaminated effluents. As a result, many studies have been developed aiming at new efficient methodologies for the decontamination of these effluents. Adsorption has been widely used in the treatment of textile effluents with the use of magnetic nanomaterials that work as adsorbents for textile dyes and are easily removed from the medium, through the application of an external magnetic field. In this work, iron oxide magnetic nanoparticles (NPs) with average crystallite size between 30 and 35 nm were synthesized. These NPs were used as adsorbents for Reactive Black 5 (RB5) dye residues in aqueous medium. The decolorization and removal efficiencies of RB5 by the NPs were around 100% and 40%, respectively. The adsorption kinetics was better adjusted to the Pseudo Second Order method with correlation coefficient R2 = 0,95. For the adsorption isotherms, the Langmuir and Freundlich models were satisfactorily adjusted to the results obtained.Item Análise do processo adsortivo de corantes industriais por nanopartículas magnéticas de magnetita (Fe3O4)(2019-07-08) Cabral, Ariane Nathália de Siqueira Souza; Araújo, Ana Cláudia Vaz de; http://lattes.cnpq.br/6861890992609511; http://lattes.cnpq.br/3246406733304902Environmental degradation is an inevitable factor that accompanies the development of the population and unfortunately this has reached water systems, rivers and water sources. Among the agents that contribute to the contamination and degradation are the dyes from the textile and food industries that are discarded throughout the production processes. There are several methods being developed to eliminate the effluent dyes in rivers and springs, among which is the adsorption process. The magnetic nanoparticles of magnetite (Fe3O4) have been previously tested in the adsorption of dye residues from the textile and food industries. In this context, the objective of this work was to study the efficiency of magnetic nanoparticles of magnetite (NPs) in the adsorption process of some dyes present in industrial textile effluents, such as dyes, methyl orange (MEL) and methylene blue (AM) . A factorial design 2³ was established obtaining as factors studied time, pH and temperature, and for these factors its levels were analyzed. Analyzes were made for systems under ultrasound and under magnetic stirring, and for this, significant results were obtained for the two dyes. According to the results obtained for the ALM / NPs, factors such as time and pH with greater significance. It was observed that the most successful tests for adsorption were the tests 02 (11,362) and 06 (10,057), for the systems under ultrasound and under magnetic stirring, respectively. For the AM / NPs it was significant only the factor, time. The most favorable tests for the dye adsorption system were 04 (19,144) and 06 (21,457), for systems under ultrasound and under magnetic stirring, respectively.Item Produção de nanopartículas magnéticas aplicada ao processo de tratamento de efluentes oriundos das indústrias têxteis(2018-08-27) Damasceno, Bárbara Souza; Araújo, Ana Cláudia Vaz de; http://lattes.cnpq.br/6861890992609511; http://lattes.cnpq.br/6533105269743189Iron oxide magnetic nanoparticles (NPs) were synthetized by chemical coprecipitation method under ultrasound. Synthetized NPs were characterized by X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, porosimetry and magnetometry. The crystalline phase of the obtained NPs was identified as maghemite and the crystallite average size was estimated by Scherrer equation around 31.5 nm. The FTIR spectra presented distinct absorptions bands at corresponding to intrinsic stretching vibrations of Fe–O bond at the iron oxides. Langmuir and BET surface areas of as-formed samples is 220,15 ± 19,81 m2 g-1 and 127,19 ± 4,94 m2 g-1 respectively. NPs samples present ferromagnetic behavior and saturation magnetization (SM) value of 46 emu g-1. Adsorption performances on synthetized and commercial nanoparticles were investigated and compared. The influences of parameters including pH, dye concentration, and agitation time have been investigated in order to find the optimum adsorption conditions. Parameters as pH 4.0, with 150 min of contact time and dye concentration of 20 mg L-1 were chosen. Adsorption results indicate that the isotherm and kinetics for dye adsorption on NPs obey Freundlich isotherm and pseudo-second-order kinetic, respectively. The maximum dye (20 mg·L-1) removal efficiency to maghemite NPs was found to be 43% and to commercial magnetite NPs was 33%. For the same experimental conditions, maghemite also had better application of the available area for adsorption than the magnetite NPs, presenting values of 8.80 mg g-1 and 6.12 mg g-1, respectively.