Estudo da cinética de decomposição térmica das sínteses pelos métodos Pechini e gelatina dos óxidos cerâmicos LaNiO3 e o LaNi0,8Co0,2O3

• Ano de defesa: 2017
• Autor(a) principal: Silva, Fabio Emanuel França da
• Tipo de documento: Dissertação
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade Federal da Paraíba; Brasil; Engenharia de Energias Renováveis; Programa de Pós-Graduação em Energias Renováveis; UFPB
• Palavras-chave em Português: Catalisadores; Métodos de síntese; Perovskita; Energia de ativação aparente; Catalysts; Synthesis methods; Perovskite; Apparent activation energy; Energias renováveis; Catalisador; CNPQ::ENGENHARIAS
• Link de acesso: https://repositorio.ufpb.br/jspui/handle/123456789/12767

The catalysts may be synthesized by different methods and these will contribute to the final characteristics of the compound from its structure to the desired applications. In this work two methods of synthesis for the preparation of catalysts with perovskite type structure, LaNiO3 and LaNi0,8Co0,2O3, by the Pechini and gelatin methods were evaluated. After the syntheses, the catalysts were calcined at 700 °C for 4 h to obtain the desired crystalline phase of the samples, which was verified with the aid of the X-ray diffraction (XRD) technique. In scanning electron microscopy (SEM) and in the specific area analysis through nitrogen adsorption (BET) it was observed that the catalysts are porous and with high surface area, respectively. With the data of the thermal analyzes, a study of the thermal decomposition of the organic matter for the synthesis methods was studied, using the non - isothermal kinetic methods of FlynnWall and Model Free Kinetics, in the heating ratios of 5, 10 and 15 °C.min-1 by initiating heating to room temperature up to 800 °C. The values of the apparent activation energies were obtained for the region of greatest organic matter decomposition in the samples that were determined as a function of the degree of conversion (α).