Usage of Biomass-based Carbon Materials as Lubricant Additive: Effects on Rheological and Tribological Properties

Abstract

Lubricating oils are thick and sticky fluids used for greasing moving parts of machines and engines. This paper expresses key advances in surface engineering and the use of biomass materials as lubricant additives. In order to enhance the lubrication characteristics of base oil, the biochar lubricant additives were successfully prepared. The tribological behaviors of biochar (biomass and hybrid) lubricant additives in two types of base oils (SN500 and SN900) were evaluated. In the current study, biomass-based carbon materials (biochar and hybrid) from a thermochemical conversion unit were employed as a lubricant additive. The rheological and tribological behavior of the base oil modified with biochar additives were experimentally determined. Surface analyses via SEM confirmed the surface enhancement of the worn exterior plane via the effect produced by the biochar additives. It was also observed that the biomass biochar using SN900 improved the kinematic viscosities of the base oil more than the hybrid biochar. This may be attributed to the chars' fundamental composition, which makes the fluid’s internal resistance flow under gravitational force. With SN500, the viscosity index improves with the biochar from 106 to108 but is reduced for SN900 from 102 to 97.09.