Characterizing Antioxidant Potential of Alcoholic Extracts of Rice Husk and Saw Dust for Oxidative Stability of Base Lubricating Oil Using Physico-chemical Properties

The thermo-oxidative stability of the mineral base oil (MBO) was examined by subjecting it to artificial aging process performed at different temperatures (25, 50, 100, 150, and 200 °C) and times (00–24 h in cycles of 06 h). The MBO samples additized with the antioxidants under study were then oxidized under the optimized temperatures and time. The antioxidants were used in concentration range of 1–3 % (w/w). The extent of the degradation was estimated from the changes in the physico-chemical properties i.e. kinematic viscosity determined at 40 and 100 °C, viscosity index, viscosity ratio, Conradson carbon residue, total acid number and iodine number in comparison with the un-oxidized plain oil. The results inferred that the antioxidants used in concentration of 3 % proved to be effective in avoiding the thermo-oxidative degradation of the MBO.