Comparison of methods for determination of oxidative stability of B100 biodiesel mixed with synthetic antioxidants: Application of simplex-centroid design with process variable [Compara??o dos métodos de determina??o da estabilidade oxidativa de biodiesel B100, em mistura com antioxidantes sintéticos. Aplica??o do delineamento simplexcentroide com variável de processo]

摘要

The Rancimat and accelerated stove tests were used to determine the oxidative stability of B100 biodiesel mixed with synthetic antioxidants. The predictive equations, with process variable, were obtained by applying a simplex-centroid design. Regardless of the antioxidant used, all assays carried out with the accelerated stove test presented storage time longer than 177.88 d, the greatest value obtained by applying the Rancimat test. The t test, applied to the parameters containing the process variable, showed a statistically signifcant difference (at the level of 5%) between the methods used.