Some Studies on the Use of Vegetable Oils as Environmentally-Friendly Lubricants

Abstract

Environmentally friendly lubricants have been gaining importance worldwide for different technical applications because of the growing concern for the environments. In this respect vegetable oils have immense potential to replace polluting mineral oil based lubricants due to their biodegradability, renewability, low toxicity and excellent lubrication performance. In this paper tribological property of two vegetable oils, namely, rapeseed oil and sunflower oil, were evaluated at different temperatures. The influence of stearic acid as an additive on the tribological properties of these vegetable oils was also investigated using four-ball tribometer. The viscosity, acid value, peroxide value and iodine value of the selected oils were determined experimentally following AOCS methods. It has been observed that stearic acid improved the antiwear properties of the vegetable oils based on formulation under boundary conditions of lubricants at different temperatures.

Keywords

• vegetable oils
• lubricants
• tribological properties
• stearic acid
• friction coefficient