Investigation on Thermo-Oxidative Stability of Karanja Oil Derived Biolubricant Base Oil

摘要

Vegetable oils lack acceptable thermo-oxidative stability due to the presence of tertiary pVhydrogen in glycerol backbone of triglyceride molecule.Chemical modification methods may significantly improve the thermo-oxidative stability of vegetable oils derivedbiolubricants without hindering their environmentally benign characteristics.This study was aimed at evaluation of thermo-oxidative stability of non-edible karanja oil derived biolubricant base oil.The biolubricant karanja oil trimethylolpropane ester(KOTMPE)was synthesized by conventional two step transesterification process.Thermal stability of synthesized product was assessed by thermogravimetric analysis in non-isothermal mode under nitrogen atmosphere,whereas the oxidation stability was analyzed using Rancimat method.Kinetics of thermal degradation of biolubricant was also investigated by thermogravimetric analysis to obtain order of thermal degradation,activation energy and the frequency factor.The results revealed excellent thermo-oxidative stability for synthesized product at high temperatures with ample scope for further improvement by blending with appropriate additives as demanded by specific applications.