Avaliação da remoção de corantes têxteis presentes em águas residuárias utilizando bagaço de cana-de-açúcar como adsorvente

• Ano de defesa: 2020
• Autor(a) principal: Xavier, Cínthia Sany França
• Orientador(a): Vieira, Fernando Fernandes
• Banca de defesa: Oliveira, Líbia de Sousa Conrado, Lima, Carlos Antônio Pereira de
• Tipo de documento: Dissertação
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade Estadual da Paraíba
• Programa de Pós-Graduação: Programa de Pós-Graduação em Ciência e Tecnologia Ambiental - PPGCTA
• Departamento: Pró-Reitoria de Pós-Graduação e Pesquisa - PRPGP
• País: BR
• Palavras-chave em Português: Secagem; Adsorção; Bagaço de cana-de-açúcar
• Palavras-chave em Inglês: Drying; Adsorption; Sugarcane bagasse
• Área do conhecimento CNPq: ENGENHARIAS
• Link de acesso: https://repositorio.uepb.edu.br/handle/123456789/72331

One of the big environmental problems is related to inappropriate waste disposal generated by the textile industries, once their contaminants cause changes in the natural conditions of the environment where they are disposed of. In this context, the adsorption process emerges as an effective treatment technique with concerning to cost, flexibility and ease operation. In this research evaluated the drying of sugarcane bagasse at temperatures of 60 and 80oC as well as your potential as a natural adsorbent for textile dyes. In the first stage of the research, the material was dried and experimental data modeling, followed by characterization of the adsorbent through the determination zero point of charge (PCZ) and Fourier transform infrared photoacoustic spectroscopy (FTIR) and the study of adsorption through experimental factorial 2^3 . Among the models used to describe the drying kinetics, the Page's model best fit the experimental data. In the evaluation of zero point of charge was verified that the adsorbent has a pHpcz equal to 3.37 for the dry material at 60 °C. In factorial design, the influence of dye concentration, contact time and adsorbent temperature was analyzed on the response variables amount of adsorbed dye (qt) and reduction of dye concentration (%red). All variables were statistically significant at the 95% confidence interval giving a maximum value for adsorbed dye of 8.34 mg.g^-1 and a dye reduction percentage of up to 83.4%. In the second stage of the research, acid and alkaline activations of the adsorbent material were performed and a Box-Behnken 2^5 experimental design for each adsorbent material having as independent variables the mass, concentration, pH, rotation and time. Kinetic tests were performed at pH 3.0 and concentration of 150 mg.L^-1 , and samples were collected every five minutes for up to 60 minutes for in natural, acid and alkaline adsorbents. The kinetic data were adjusted to the pseudo first order, pseudo second order and Elovich equation models, with the Elovich model being the best fit for the tests. The isotherms were constructed varying the concentration from 25 to 200 mg.L^-1 , with pH 3.0 and the Sips isotherm obtained higher value of R^2 and Test F. The sugarcane bagasse was attractive in removing the textile dye, especially when HCl adsorbent treatment is performed.