Tribological properties of bio-based lubricant basestock obtained from pequi oil ( Caryocar brasiliensis )

The development of basestock oil derived from renewable sources has become crucial as the world oil reserves are depleting. In this study, samples based on pequi oil ( Caryocarbrasiliensis ) were obtained by hydrolysis and esterification reactions, using a long-chain alcohol (2-ethylhexanol). Tribological tests in a four-ball configuration were performed to evaluate the lubricating behavior. A comparison of the Stribeck curve of the bio-based sample with that of a mineral hydrotreated basestock oil showed that the samples from pequi oil had a lower friction coefficient at all studied sliding speeds, ranging from 0 to 9.33 × 10 5 μm /s. The friction coefficient of the bio-based sample was 30.7% lower than that of a mineral hydrotreated basestock oil sample. The wear scar diameters were 0.371 mm for the bio-based samples and 0.195 mm for the mineral oil. This tribological performance indicates that a bio-based sample obtained from pequi oil may be potentially used as a lubricant basestock oil.