Influence of techniques on synthesizing cashew nut shell oil as a prospective biolubricant on its physicochemical, tribological, and thermal behaviors

Rising demand for lubricants and temperamental government policies hastened the need for a renewable base stock for petroleum-based lubricants. The environment-friendly alternative for conventional lubricants can be developed from non-edible vegetable oils due to its abundance all over the world and biodegradability. The present study focuses on the feasibility study of utilizing Cashew nut shell oil (CNSO) as a lubricant base stock, which is one of the cheap and abundant non-edible oil. Two different types of CNSO are being synthesized-mechanically expelled oil from the boiled cashew shell (MEO) and the oil extracted from raw cut shells (SEO). Lubricating properties such as physicochemical, tribological, thermal, corrosive, and oxidative properties are being evaluated for MEO and SEO samples. It was observed that MEO being more abundant compared with SEO, possesses a low wear scar diameter of 714 μm, better thermal properties, viscosity index, and oxidative stability. Hence MEO is a better option to be considered as a lubricant comparing SEO.