Estudo da estabilidade oxidativa do biodiesel aditivado com aminas aromáticas

• Autor(a) principal: Maciel, Gabrielly dos Santos
• Data de Publicação: 2018
• Tipo de documento: Dissertação
• Idioma: por
• Título da fonte: Biblioteca Digital de Teses e Dissertações da UFPB
• Texto Completo: https://repositorio.ufpb.br/jspui/handle/123456789/13059
• topic: Biodiesel; Antioxidante; Estabilidade oxidativa; Aminas aromáticas; Biodiesel antioxidant; Oxidative stability; Aromatic amines; CNPQ::CIENCIAS EXATAS E DA TERRA::QUIMICA

The problem related to the useful life of biodiesel stimulated this study, which involved the evaluation of aromatic amines as antioxidant additive in the retardation of the degradation process of the same. Two accelerated methods of oxidative stability quantification of biodiesel samples from three sources, namely cottonseed oil (OA), residential residual oil (ORR) and commercial residential oil (ORC) were evaluated. All the physico-chemical parameters studied for the biodiesel samples were within the limits established by the technical regulation of the National Agency of Petroleum, Natural Gas and Biofuels (ANP), N° 3/2014. First, samples of the methylated cotton biodiesel (BMA) without and containing different concentrations of 3,4-diaminotoluene (DAT) were evaluated by the PetroOxy (ASTM D7545) and Rancimat (EN 14112) methods. Induction period (PI) values showed a higher protective effect at 5.00 mmol.kg-1, regardless of the method of analysis. The 8 h value specified by the ANP, using the Rancimat method, was not only reached for the DAT sample at the concentration of 1.25 mmol.kg-1. As well as the monitoring of DAT concentration, the influence of temperature was investigated using the PetroOxy method. The extent of protection factor (PF) in the samples was temperature dependent and the highest protective effect of DAT was observed at the temperature of 110 ° C. A complementary study was carried out with samples of BMA, BMRR and commercial (BMRC), without and with DAT, N-phenyl-o-phenylenediamine (DNO), Nphenyl-p-phenylenediamine (DNP) and diphenylamine (DIF) at the concentration of 5 mmol.kg-1 by the Rancimat and PetroOxy method (90,100,110 and 120 ° C). The analysis of the obtained results allowed to conclude that the aromatic amines reached a satisfactory protective effect against the auto-oxidation of the biodiesel, however the FP of the aromatic amine depended on the temperature and the type of biodiesel, as well as the method of analysis. However, in general, the amines DNO and DNP, which are the work differential, showed higher PF values than the DAT and DIF amines. In addition, PI values were higher than those regulated by the ANP, when evaluated by the Rancimat method, except the BMA and BMRR samples supplemented with DIF and BMRR with DNP.