Estudo da estabilidade oxidativa do biodiesel de babaçu e soja

Abstract

The biodiesel is a biofuel prominent, because of the ability to partially or totally replace the diesel fuel with the advantages of being a clean fuel, however, biodiesel is subject to oxidative degradation, thus the study of the different oxidative stability of biodiesel and great importance for technological development. The oxidative degradation occurs due to the action of air, light, temperature and humidity with this fast-paced action when biodiesels are exposed to elevated temperatures or in contact with catalytic agents. The present work aims to study the stability of biodiesel produced from vegetable oil babassu and soybean. To study the stability of biodiesels samples were subjected to thermal stress in an oven at 130 ° C for a period of 8 hours. The analyzes performed to monitor the level of oxidation of biodiesels were analysis of acid value, refractive index and techniques UV-Vis spectroscopy and infrared. The study was also addressed catalytic effects of metals on the oxidation of soybean biodiesel and biodiesel from babassu comparing the effect of metal relative to biodiesel without the metal. The results obtained by the acid number indicated an increase as time since index of heat stress in soybean biodiesel and biodiesel from babassu, also the catalytic effect of iron and copper was found in soy biodiesel and less intensively in biodiesel babassu. Analyzing the refractive index of pure biodiesel with babassu biodiesel babassu not contaminated with metal is a significant difference between the refractive indices. Changes in UV-Vis spectra of babassu biodiesel are lower intensity compared to soybean biodiesel indicating greater stability of biodiesel from babassu. Infrared spectra indicated that the biodiesel Babassu suffers little change when compared to soybean, indicating a higher resistance to the formation of oxidation products characteristic of the area studied.