A Thermal Characteristics Study of Typical Industrial Oil Based on Thermogravimetric-Differential Scanning Calorimetry (TG-DSC)

Abstract

Recent incidents of fire accidents attributed to oil combustion have emerged as a significant threat to both industrial safety and environmental conservation. In this study, the thermal oxidation and thermal analysis kinetics parameters of transformer oil, engine oil, and hydraulic oil in the air atmosphere were explored based on thermogravimetric-differential scanning calorimetry (TG-DSC). Industrial oils showed the same decomposition process in the thermal decomposition process. The peak temperature of the DSC curve was higher than that of the DTG curve, and the peak values of DTG and DSC curves increased with the increase of heating rate. The industrial oils underwent a main mass loss process, with respective ranges of approximately 80–84% for transformer oil, 73–79% for engine oil, and 86–89% for hydraulic oil. Notably, engine oil demonstrated the highest average apparent activation energy, amounting to 110.50 kJ/mol, significantly surpassing hydraulic oil (105.13 kJ/mol) and transformer oil (60.95 kJ/mol). The optimal kinetic model for the evaporative oxidation reaction of the industrial oils in air was identified as the reaction order model (Fn), with the corresponding kinetic mechanism function expressed as f(α) = (1 − α)n. The use of TG-DSC offers novel perspectives on the thermal stability and safety evaluation of oil products. Meanwhile, the optimal kinetic model and thermal oxidation stability of typical industrial oil evaporation and oxidation reaction in air was determined, possessing a good reference for the safety and the application of industrial oil.