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Highlights: [•] Sunflower- and soybean-based biodiesels were synthesized by transterification. [•] Stability to oxidation was determined using ASTMD 7545 method. [•] Ionol BF 200 was and effective inhibitor for biodiesel oxidation. [•] Antioxidant oxidation kinetics was of first order for soybean biodiesel. [•] Oxidation kinetics was apparently of zero-order for sunflower biodiesel. [Copyright &y& Elsevier]

This study developed a methodology for converting hydrogenated cardanol, a compound extracted from cashew nut shell liquid into compounds with structural characteristics of antioxidants similar to the ones used in products derived from petroleum. The intended changes were carried out through exhaustive alkylation with tert-butyl chloride. The performance of the products was estimated in terms of oxidative stabilization during storage of cracked naphtha samples collected from the outlet of an industrial unit. The compound 2,4,6-tri-t-butyl-pentadecylphenol (new antioxidant) has presented a better efficiency in the storage assays as compared to the commercial additive used as reference in the refinery at the moment of sampling. [Copyright &y& Elsevier]

In this manuscript, the kinetics of oxidation of canola oil-based biodiesel were investigated using the PetroOXY method (ASTM D7545) at different pressures (350, 700, and 715 kPa). The examined temperature range was 130–145 °C, with Ionol BF200 antioxidant concentration varying from 0 to 4000 ppm. An apparent activation enthalpy was calculated from the Arrhenius equation, yielding apparent enthalpies that were independent of oxygen pressure, of around 100 kJ/mol. Critical antioxidant concentrations for biodiesel destabilization were independent of temperature and increased as pressure was decreased. When compared to the Rancimat method for analysis of biodiesel oxidation, the PetroOXY method was considered a better alternative, requiring analysis times as low as 1/20 of the time spent using the Rancimat method. [ABSTRACT FROM AUTHOR]