Coconut Oil as Bio Lubricant: Study of the Anti-Wear Properties Using Quantum Chemical Calculations and Tribological Tests

In this paper Spartan 02, a molecular dynamics software is used to analyze and predict the tribological properties of coconut oil in a qualitative manner on the basis of carbon chain length of the constituent fatty acids, their polarity (Net electrostatic charge, Q_r) and the energies of the molecular orbitals E_HOMO (Energy of the Highest Occupied Molecular Orbital) and E_LUMO (Energy of the Lowest Unoccupied Molecular Orbital) and the enthalpies of formations (H_form) of the iron soaps of respective fatty acids. Tribological properties of the constituent fatty acids of coconut oil were evaluated using a four-ball tester as per ASTM D4172 method. The experimental results showed good correlation to the selected quantum chemical descriptors. The influence of an anti-wear additive on the tribological performance of coconut oil and the optimum additive concentration were also evaluated experimentally.