Novas abordagens para análise de dados de interações em interfaces sólido/solução

• Ano de defesa: 2012
• Autor(a) principal: Santos, Elisio Cristovão Souza dos
• Orientador(a): Cestari, Antônio Reinaldo
• Tipo de documento: Dissertação
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade Federal de Sergipe
• Programa de Pós-Graduação: Pós-Graduação em Ciência e Engenharia de Materiais
• País: BR
• Palavras-chave em Português: Sorção; Modelagem; Interface sólido/solução
• Palavras-chave em Inglês: Sorption; Modeling; Solid/solution interfaces
• Área do conhecimento CNPq: CNPQ::ENGENHARIAS::ENGENHARIA DE MATERIAIS E METALURGICA
• Link de acesso: https://ri.ufs.br/handle/riufs/3520

In this work, innovative approaches of sorption data at solid/solution interfaces were shown. Firstly, sorption data of a yellow dye on sílica-aminopropyl were evaluated. The experimental data were well fitted to the sorption models in equilibrium of Langmuir, Langmuir-Freundlich e Sips. It was concluded that some values of the sorption equilibrium constants (Keq) of this sorption process were inadequate, since their numerical values were too low, which is not in agreement with high-performance chemically-stable sorption processes. Sorption data of a remazol blue dye on a silica/chitosan hybrid were evaluated using an innovative methodology proposed by Azizian. From this model, values of Keq can be calculated using sorption kinetic data of a given sorption system. The Azizian model was well fitted to the experimental data of this sorption system. In addition, it was observed that the values of Keq were all high in nature and decreased as temperature increases. The Azizian methodology was also tested in sorption data of the remazol dyes yellow, blue and red on Epichlorohydrin crosslinked chitosan spheres. However, the Azizian model was not fitted properly, due probably to changes of the value of Keq in relation to initial dye concentration in solution. An innovative methodology using the microcalorimetry technique was used to evaluate the sorption of the methylene blue dye on fish scales of Robalo fish. The kinetic data was well fitted to a three-parameter kinetic model. However, the Azizian model was also not fitted to this sorption system, due also to changes of the value of Keq in relation to initial dye concentration in solution. It was concluded that the choice of a given sorption model is important in order to calculate correct sorption parameters. In general, the Azizian methodology is promising to calculate the equilibrium constant values from kinetic data. It is believed that the contributions from this Dissertation are important in order to propose new ways to calculate and to understand sorption phenomena at solid/solution interfaces.