Escamas de peixe pescada amarela (Cynoscion acoupa) modificadas com glutaraldeído e aminas para remoção de doxiciclina em meio aquoso

• Ano de defesa: 2017
• Autor(a) principal: Lemos, Jéssica Aline Santos
• 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 Química
• País: Brasil
• Palavras-chave em Português: Química; Cinética química; Adsorção; Peixe; Glutaraldeído; Aminas; Materiais adsorventes; Escamas de peixe; Doxiciclina; Sorção em solução
• Palavras-chave em Inglês: Adsorbent materials; Fish scales; Doxycycline; Sorption from solution; Chemical kinetics
• Área do conhecimento CNPq: CIENCIAS EXATAS E DA TERRA::QUIMICA
• Link de acesso: https://ri.ufs.br/handle/riufs/6072

Adsorbent materials have been used to efficiently remove several chemical harmful compounds from water bodies. Searching to develop low-cost adsorbent materials, this work describes the features of new adsorbent materials using fish scales chemically modified with glutaraldehyde (GA) and amines in three sequential step reactions, as well as to apply the materials to remove doxycycline (DOX) from aqueous media. All adsorbents were characterized before and after DOX sorption. Thermal analysis by TG/DTG have shown increasing of thermal stability of the adsorbents, due mainly to cross-linking reactions by GA. Elementary analysis has shown increasing of carbon and nitrogen amounts in relation to the starting material. FTIR spectra have shown increasing of N-H and O-H stretching bands after chemical modifications of the scales. MEV micrographies have suggested changes of the surfaces of the adsorbents in relation to the pristine material, due probably to structural changes of fibrillar collagen on the scales. The presence of DOX was also clearly evidenced by characterization. The best results for the DOX sorption were obtained at 25°C, using solutions of DOX of initial concentration of 2.5x10 -5 mol L -1 , obtaining maximum DOX sorbed amounts of about 3.2 mol/g. The best DOX desorption results were obtained using aqueous solutions at pH of 4.0. The kinetic data of DOX sorption were best fitted to an order- variable kinetic model. The analysis of the kinetic results has indicated DOX sorption as exothermic in nature, with DOX interactions using most external sorption sites of the adsorbents as the main DOX sorption mechanism. The results have shown that GA/amines-chemically modified fish scales are promising materials for efficient removal of DOX from aqueous media.