Confecção e caracterização de membranas funcionalizadas com Ni-ZnO/casca de ovo para uso em processos de separação de proteínas

• Autor(a) principal: Oliveira, Luma de
• Data de Publicação: 2022
• Tipo de documento: Dissertação
• Idioma: por
• Título da fonte: Biblioteca Digital de Teses e Dissertações do UNIOESTE
• Texto Completo: https://tede.unioeste.br/handle/tede/6234
• topic: Processo de separação por membranas; Compósitos; Resíduo sólido; Sustentabilidade; Proteínas; Fouling; Membrane separation process; Composites; Solid residue; Sustainability; Proteins; ENGENHARIA QUIMICA::PROCESSOS INDUSTRIAIS DE ENGENHARIA QUIMICA

The objective of this work was the fabrication and characterization of functionalized polymeric membranes with composite synthesized from the combination of Ni-ZnO and chicken eggshell (COG) for use in separation processes. Therefore, polymeric polysulfone membranes were prepared by the phase inversion method and functionalized on the surface (ME) and in the polymeric dispersion (MI) with 1% of the Ni-ZnO/COG composite in the preliminary tests and with 1% and 2.5 % Ni-ZnO/COG in tests with membranes with different concentrations of composite. In the preliminary tests, the compaction and filtration of the proteins egg albumin, hydrolyzed collagen and type II collagen were carried out, while in the tests using membranes with different concentrations of composite, the compaction and filtration of type II collagen were carried out. Three cleaning methods were developed (Method A, B, C) and used under different operating conditions. In addition to the filtration tests, the functionalized membranes with different concentrations of composite (M0%, ME 1%, ME 2.5%, MI 1% and MI 2.5%), COG, Ni-ZnO and Ni- ZnO/COG were characterized by thermal, mechanical, surface, morphological and structural analyses. For the membrane that presented the best results, the study of the influence of type II collagen concentration (0,1; 0,5 e 1,0 g L-1) and fouling was carried out. The results showed that the Ni-ZnO/COG composite showed high thermal stability up to 250 ºC, with the presence of CaCO3 and ZnO in its structure being identified. The functionalized membranes showed higher porosity, water absorption and hydrophilicity, and high values of permeate flux (approximately 3700 Kg m-2 h-1), compared to the membrane without the composite insert (M 0%). The average rejection obtained by the functionalized membranes with different concentrations of composite was approximately 55%. Membrane cleaning with Methods A and B proved to be inefficient for all manufactured membranes (Firrev > 59% and Ft > 80%). Method C proved to be efficient with irreversible fouling values lower than 15% and flow recovery higher than 85%. Among the membranes with different levels of composite, the ME 2.5% was the one that presented the best results, being evaluated in it the influence of the type II collagen concentration (0.1; 0.5 and 1.0 g L-1). It was observed that the permeate flux was inversely proportional to the type II collagen concentration, while membrane rejection was directly proportional to this concentration. Furthermore, it was found that the ME 2.5% membrane can be reused for 3 cycles (Method C), as it maintains a high flow recovery value (>83%) with low irreversible fouling (<17%). Therefore, the results obtained in this study show that with the insertion of eggshell, an industrial waste, it was possible to obtain a composite with favorable functionalization characteristics, thus improving the concept of sustainability of the process. In addition, membranes functionalized with Ni-ZnO/COG showed to be promising for application in protein separation processes.