Performance of pure palm oil and palm oil ester as lubricant / Khairul Syazwani Shahrudin

The use of renewable resources is one of the alternatives to overcome the dependencies on mineral oils. Vegetable oil and esters produced from vegetable oils are potential biodegradable lubricant. The use of palm oil as refine palm olein and industrial palm oil ester bio-based which are palmester 2083 trimethylolpropane trioleate and palmester 2090 trimethylolpropane trioleate as lubricants was investigated. The physical characteristics of both lubricants such as viscosity, viscosity index (VI) and acid value were determined through viscosity test. The tribological properties of all lubricants which included coefficient of friction and wear characteristics were tested by using four ball machine and pin on disc machine. The test was implemented using 40 kg of load for four ball test and 50N for pin on disc friction test. Wear scar diameter and coefficient of friction of palm oil ester bio-based were analysed and compared to palm olein. The coefficient of friction of palmester 2083 trimethyolpropane trioleate obtained was 34.4% higher and 5% reduction in wear scar diameter compared to palm olein while palmester 2090 trimethyolpropane trioleate obtained 30% better coefficient of friction and 4 .5% reduction in wear scar diameter compared to palm olein. However, palm olein showed better worn surface than other lubricants. Palm olein also provided better lubrication through friction test by using pin on disc machine as it transited mixed lubrication regime to elastohydrodynamic lubrication regime at low coefficient of friction. As a conclusion, palm olein has good anti wear properties compared to both palmester lubricants but the coefficient of friction for all lubricants shows contra result for four ball test and pin on disc test.