Influence of a halogen free ionic liquid on the rheological and tribological characteristics of canola oil

Abstract

Purpose This paper aims to develop vegetable oil-based environmentally acceptable lubricants with a halogen-free ionic liquid (IL) as a substitute for petroleum-based lubricants. Design/methodology/approach The rheological and tribological characteristics of canola oil influenced by 1-ethyl-3-methylimidazolium dicyanamide as an additive along with surfactants have been experimentally investigated. The viscosities of prepared bio-ionic lubricants have been evaluated at a constant shear rate of 100 per second with a temperature ramp from 30°C to 100°C and also by varying shear rate from 1 to 103 per second at constant temperatures of 40°C and 100°C. The solubilization and absorbance of bio-ionic lubricants have been studied by using dynamic light scattering and ultraviolet–visible spectroscopy. Friction and wear effects of bio-ionic lubricants have been evaluated using ball-on-disc tribotester at different speeds and loads. Findings The rheological properties of canola oil have been significantly improved with addition of IL. Minimum coefficient of friction and wear have been observed at an optimum concentration of 2 Wt.% of IL. Atomic force microscopy reveals that worn-out surface of ball lubricated with canola oil containing 2 Wt.% IL has smooth surface. Originality/value This study demonstrates that halogen-free has the potential to accommodate as an incipient class of EALs.