Development of bio-based lubricant from modified desert date oil (balanites aegyptiaca) with copper nanoparticles addition and their tribological analysis

Abstract

Based on the environmental concerns related to the pollution caused by the vehicles and the demand for an alternative to the conventional lubricant resulted in the studies to be conducted that are environmental-friendly. In this study, friction and wear behavior of the surfaces in contact was conducted to observe their tendency during the application of an alternative lubricant to the mineral oil. Desert date oil was having the potential of an alternative to the mineral oil and they were available in abundant amount. During the initial stage, desert date oil was transesterified using the two-step transesterification process and further it was added to the trimethylolpropane. After this process, nanoparticles were added in different amounts to the modified desert date oil. The friction and wear behavior of the modified desert date oil was tested using four-ball tester under different conditions. For the surface topography analysis, SEM and EDS analysis were conducted. The concentration of the nanoparticles added to the biolubricant was considered based on the previous work conducted. The input parameters which were considered during the test consists of normal load, sliding speed, variation in the addition of the nanoparticles to the biolubricant (0.3–1.6% with a gap of 0.3%). Based on the study conducted, 0.9% concentration of the copper nanoparticles showed a significant improvement in term of reducing COF, wear rate, mean wear scar diameter and improved worn surface morphology was obtained with comparison to the mineral oil. The maximum increment in the properties relative to the tribological analysis was shown when the concentration of the copper nanoparticles to the modified desert date oil increases beyond 0.9% copper nanoparticles during the addition in the amount of 1.3% and 1.6%. Conclusively, the performance of the modified desert date oil with 0.9% copper nanoparticles addition has the potential impact as a lubricant with comparison to the mineral oil and other samples. The modified desert date oil with an application of 0.9% copper nanoparticles could be considered as a suitable alternative to the mineral oil while considering environmental concern and energy saving.