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.