Eventos Anais de eventos
ENCIT 2018
Brazilian Congress of Thermal Sciences and Engineering
SOYBEAN AND SUNFLOWER BIODIESELS: EVALUATION OF OXIDATIVE STABILITY BY RANCIMAT AND DSC
Submission Author:
Igor de Mesquita Figueredo , CE , Brazil
Co-Authors:
Igor de Mesquita Figueredo, Maria Alexsandra de Sousa Rios
Presenter: Igor de Mesquita Figueredo
doi://10.26678/ABCM.ENCIT2018.CIT18-0756
Abstract
The biodiesel has a low oxidative stability compared to mineral diesel. Focusing on this problem, the goal of this work was evaluated the oxidative stability of soybean (BSy) and sunflower (BSf) biodiesels comparing two methods used for this purpose: Rancimat and Differential Scanning Calorimetry (DSC). In addition, this work aimed to evaluate the kinetic parameters involved in the oxidative degradation of biodiesel. In the methodology, both biodiesels were produced by a methyl route and characterized according to the National Agency of Petroleum, Natural Gas and Biofuels (ANP) rules. The results showed that most of the measured properties were in accordance to the Resolution N°45/2014. Regarding oxidative stability by the Rancimat test, the induction period (IP) was 4.80 hours for BSy and 1.73 hours for BSf. By DSC, the beginning of the oxidation process was at 458.85 K for BSy and 453.14 K for BSf. The kinetic results showed the activation energy (Ea) was higher for BSy compared to BSf and the opposite for the oxidized biodiesels (RBSy and RBSf). Based on oxidation resistance results, the BSy was more stable than BSf. The DSC showed advantages, because it does not require a large quantity of sample, takes 1 hour to complete the whole analysis, depending on the heating rate, and it is already used to determine the thermal behavior of biodiesel.
Keywords
biodiesel, Oxidative Stability, Rancimat, Differential Scanning Calorimetry, kinetic
