Study of pressure and temperature influence on rapeseed biodiesel oxidation kinetics using PetroOXY method

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 715kPa). The examined temperature range was 130–145°C, with Ionol BF200 antioxidant concentration varying from 0 to 4000ppm. An apparent activation enthalpy was calculated from the Arrhenius equation, yielding apparent enthalpies that were independent of oxygen pressure, of around 100kJ/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.