A Preliminary Investigation of Physicochemical, Rheological and Tribological Properties of Bio-lubricant from Thevetia Peruviana Oil

The present work is a comparative evaluation of physicochemical, rheological, thermal, and tribological properties of Thevetia Peruviana oil (TPO) as bio-lubricant. The tribological properties were investigated by a four-ball tribo-tester according to ASTM 4172-94 and ASTM D2783 standard. The corresponding results were compared with sunflower oil, jatropha oil, SAE 20W-40 and ISO VG 46. The acid value, pour point and flash point of TPO were found to be 1.383±0.015 mg KOH, -4±0.231°C and 344±0.04°C respectively. The viscosity index of TPO is 235.59 with viscosities 31.76 mm2/s at 40°C and 7.89 mm2/s at 100°C. The oxidation onset temperature of TPO having a value of 282.20°C is comparable to SAE 20W-40 but higher than that of ISO VG 46. The results obtained from tribological test show that TPO has low coefficient of friction 0.0496±0.001 with wear scar diameter 0.462±0.001 mm. Despite the low pour point temperature, TPO are comparable to commercial lubricants, which prove its suitability as bio-lubricant base-stock based on physicochemical, thermal, tribological properties, and high viscosity index.