Evaluation of thermal oxidation of vegetable oils by the means of safety calorimeter SEDEX

Evaluation of self-heating propensity of vegetable oils can be useful for determination of critical parameters of the system (porous material – vegetable oil), which must be fulfilled to achieve spontaneous ignition. However, the results strongly depend on the preparation of the sample and the type of method used for the evaluation of self-heating propensity of the oil. The safety calorimeter SEDEX was used to determine the selfheating propensity of three different vegetable oils tested under dynamic and adiabatic heating conditions. The calorimeter allows the use of large samples up to 15 ml, which was necessary to provide enough space for porous carrier which was wetted by oil. Three edible vegetable oils (linseed, sesame and sunflower oil) soaked in cotton were examined by the means of sequential DTA in the safety calorimeter SEDEX. First, the samples were heated from room temperature to 350°C, at heating rate 45 K/h, and then from room temperature to 200°C, at heating rate 10 K/h, to determinate the onset temperature of first exothermic reaction. Based on these results, the samples were investigated by the means of Accelerating Rate Calorimetry.